{"id":"CVE-2025-14009","aliases":["ALPINE-CVE-2025-14009","DEBIAN-CVE-2025-14009","EUVD-2025-207820","GHSA-7p94-766c-hgjp","PYSEC-2026-96","ROOT-APP-PYPI-CVE-2025-14009","UBUNTU-CVE-2025-14009","USN-8214-1","openSUSE-SU-2026:10226-1"],"status":"published","title":"Zip Slip Vulnerability in nltk/nltk Leading to Remote Code Execution","description":"A critical vulnerability exists in the NLTK downloader component of nltk/nltk, affecting all versions. The _unzip_iter function in nltk/downloader.py uses zipfile.extractall() without performing path validation or security checks. This allows attackers to craft malicious zip packages that, when downloaded and extracted by NLTK, can execute arbitrary code. The vulnerability arises because NLTK assumes all downloaded packages are trusted and extracts them without validation. If a malicious package contains Python files, such as __init__.py, these files are executed automatically upon import, leading to remote code execution. This issue can result in full system compromise, including file system access, network access, and potential persistence mechanisms.","severity":{"version":"3.0","score":10,"vector":"CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H","level":"critical","assessor":"cna","from":"cve"},"epss":{"day":"2026-11-10","score":0.01036,"percentile":0.64182,"model":"v2026.06.15"},"facts":{"in_kev":false,"known_exploited":false,"public_exploit":false,"fix_available":true},"cwes":["CWE-94"],"published":"2026-02-18T17:45:17Z","modified":"2026-11-03T06:33:00Z","fixes":[{"ecosystem":"PyPI","package":"nltk","fixed_in":["3.9.3"],"sources":["ghsa","osv"]},{"ecosystem":"Alpine:v3.24","package":"py3-nltk","fixed_in":["3.9.3-r0"],"sources":["osv"]},{"ecosystem":"Debian:14","package":"nltk","fixed_in":["3.9.3-1"],"sources":["osv"]},{"ecosystem":"Root:PyPI","package":"nltk","fixed_in":["3.9.2+aikido.7","3.9.2+aikido.8"],"sources":["osv"]},{"ecosystem":"Root:PyPI","package":"rootio-nltk","fixed_in":["3.9.2+root.io.1","3.9.2+root.io.2","3.9.2+root.io.3","3.9.2+root.io.4","3.9.2+root.io.5"],"sources":["osv"]},{"ecosystem":"Ubuntu:Pro:14.04:LTS","package":"nltk","fixed_in":["2.0~b9-0ubuntu4.1~esm5"],"sources":["osv"]},{"ecosystem":"Ubuntu:Pro:16.04:LTS","package":"nltk","fixed_in":["3.1-1ubuntu0.1+esm3"],"sources":["osv"]},{"ecosystem":"Ubuntu:Pro:18.04:LTS","package":"nltk","fixed_in":["3.2.5-1ubuntu0.1+esm3"],"sources":["osv"]},{"ecosystem":"Ubuntu:Pro:20.04:LTS","package":"nltk","fixed_in":["3.4.5-2ubuntu0.1~esm3"],"sources":["osv"]},{"ecosystem":"Ubuntu:Pro:22.04:LTS","package":"nltk","fixed_in":["3.7-1ubuntu0.1~esm1"],"sources":["osv"]},{"ecosystem":"Ubuntu:Pro:24.04:LTS","package":"nltk","fixed_in":["3.8.1-1ubuntu0.1~esm1"],"sources":["osv"]},{"ecosystem":"Ubuntu:Pro:26.04:LTS","package":"nltk","fixed_in":["3.9.2-1ubuntu0.1~esm1"],"sources":["osv"]},{"ecosystem":"openSUSE:Tumbleweed","package":"python-nltk","fixed_in":["3.9.1-3.1"],"sources":["osv"]}],"affected":[{"source":"ghsa","ecosystem":"PyPI","package":"nltk","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"last_affected":"3.9.2"},{"fixed":"3.9.3"}]}]},{"source":"osv","ecosystem":"Alpine:v3.24","package":"py3-nltk","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"3.9.3-r0"}]}]},{"source":"osv","ecosystem":"Debian:12","package":"nltk","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["3.10.0-1","3.10.1-1","3.10.3-1","3.8-1","3.8.1-1","3.9.1-1","3.9.1-2","3.9.2-1","3.9.3-1"]},{"source":"osv","ecosystem":"Debian:13","package":"nltk","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["3.10.0-1","3.10.1-1","3.10.3-1","3.9.1-2","3.9.2-1","3.9.3-1"]},{"source":"osv","ecosystem":"Debian:14","package":"nltk","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"3.9.3-1"}]}],"versions":["3.9.1-2","3.9.2-1"]},{"source":"osv","ecosystem":"PyPI","package":"nltk","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"3.9.3"}]}],"versions":["0.8","0.9","0.9.3","0.9.4","0.9.5","0.9.6","0.9.7","0.9.8","0.9.9","2.0.1","2.0.1rc1","2.0.1rc2-git","2.0.1rc3","2.0.1rc4","2.0.2","2.0.3","2.0.4","2.0.5","2.0b4","2.0b5","2.0b6","2.0b7","2.0b8","2.0b9","3.0.0","3.0.0b1","3.0.0b2","3.0.1","3.0.2","3.0.3","3.0.4","3.0.5","3.1","3.2","3.2.1","3.2.2","3.2.3","3.2.4","3.2.5","3.3","3.4","3.4.1","3.4.2","3.4.3","3.4.4","3.4.5","3.5","3.5b1","3.6","3.6.1","3.6.2","3.6.3","3.6.4","3.6.5","3.6.6","3.6.7","3.7","3.8","3.8.1","3.9","3.9.1","3.9.2","3.9b1"]},{"source":"osv","ecosystem":"PyPI","package":"nltk","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"3.9.3"}]}],"versions":["0.8","0.9","0.9.3","0.9.4","0.9.5","0.9.6","0.9.7","0.9.8","0.9.9","2.0.1","2.0.1rc1","2.0.1rc2-git","2.0.1rc3","2.0.1rc4","2.0.2","2.0.3","2.0.4","2.0.5","2.0b4","2.0b5","2.0b6","2.0b7","2.0b8","2.0b9","3.0.0","3.0.0b1","3.0.0b2","3.0.1","3.0.2","3.0.3","3.0.4","3.0.5","3.1","3.2","3.2.1","3.2.2","3.2.3","3.2.4","3.2.5","3.3","3.4","3.4.1","3.4.2","3.4.3","3.4.4","3.4.5","3.5","3.5b1","3.6","3.6.1","3.6.2","3.6.3","3.6.4","3.6.5","3.6.6","3.6.7","3.7","3.8","3.8.1","3.9","3.9.1","3.9.2","3.9b1"]},{"source":"osv","ecosystem":"Root:PyPI","package":"nltk","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"3.9.2+aikido.7"},{"fixed":"3.9.2+aikido.8"}]}]},{"source":"osv","ecosystem":"Root:PyPI","package":"rootio-nltk","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"3.9.2+root.io.1"},{"fixed":"3.9.2+root.io.2"},{"fixed":"3.9.2+root.io.3"},{"fixed":"3.9.2+root.io.4"},{"fixed":"3.9.2+root.io.5"}]}]},{"source":"osv","ecosystem":"Ubuntu:Pro:14.04:LTS","package":"nltk","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"2.0~b9-0ubuntu4.1~esm5"}]}],"versions":["2.0~b9-0ubuntu4","2.0~b9-0ubuntu4.1~esm2","2.0~b9-0ubuntu4.1~esm4"]},{"source":"osv","ecosystem":"Ubuntu:Pro:16.04:LTS","package":"nltk","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"3.1-1ubuntu0.1+esm3"}]}],"versions":["3.0.4-1","3.0.5-1","3.1-1","3.1-1ubuntu0.1","3.1-1ubuntu0.1+esm1","3.1-1ubuntu0.1+esm2"]},{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hat","product":"openshift lightspeed"},{"vendor":"red hat","product":"red hat openshift ai (rhoai)"},{"vendor":"red hat","product":"red hat openshift ai 2.25"}],"references":[{"url":"https://huntr.com/bounties/49ecbc02-054e-4470-b2e0-b267936cc4e4","tags":["exploit","Exploit","Third Party 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Slip Vulnerability in nltk/nltk Leading to Remote Code Execution","description":"A critical vulnerability exists in the NLTK downloader component of nltk/nltk, affecting all versions. The _unzip_iter function in nltk/downloader.py uses zipfile.extractall() without performing path validation or security checks. This allows attackers to craft malicious zip packages that, when downloaded and extracted by NLTK, can execute arbitrary code. The vulnerability arises because NLTK assumes all downloaded packages are trusted and extracts them without validation. If a malicious package contains Python files, such as __init__.py, these files are executed automatically upon import, leading to remote code execution. This issue can result in full system compromise, including file system access, network access, and potential persistence mechanisms.","status":"published","published":"2026-02-18T17:45:17.573Z","modified":"2026-07-15T01:27:23.097Z","cvss":[{"version":"3.0","score":10,"vector":"CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H","level":"critical","assessor":"cna"},{"version":"3.1","score":8.8,"vector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H","level":"high","assessor":"adp"}],"cwes":["CWE-94","CWE-94"],"updated_at":"2026-11-02T14:32:28.621398Z"}],"euvd":[{"id":"EUVD-2025-207820","description":"A critical vulnerability exists in the NLTK downloader component of nltk/nltk, affecting all versions. The _unzip_iter function in nltk/downloader.py uses zipfile.extractall() without performing path validation or security checks. This allows attackers to craft malicious zip packages that, when downloaded and extracted by NLTK, can execute arbitrary code. The vulnerability arises because NLTK assumes all downloaded packages are trusted and extracts them without validation. If a malicious package contains Python files, such as __init__.py, these files are executed automatically upon import, leading to remote code execution. This issue can result in full system compromise, including file system access, network access, and potential persistence mechanisms.","status":"published","published":"2026-02-18T17:45:17Z","modified":"2026-07-15T01:27:23Z","cvss":[{"version":"3.1","score":8.8,"vector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H","level":"high"}],"updated_at":"2026-11-02T18:19:53.678292Z"}],"ghsa":[{"id":"GHSA-7p94-766c-hgjp","title":"NLTK has a Zip Slip Vulnerability","description":"A critical vulnerability exists in the NLTK downloader component of nltk/nltk, affecting all versions. The _unzip_iter function in nltk/downloader.py uses zipfile.extractall() without performing path validation or security checks. This allows attackers to craft malicious zip packages that, when downloaded and extracted by NLTK, can execute arbitrary code. The vulnerability arises because NLTK assumes all downloaded packages are trusted and extracts them without validation. If a malicious package contains Python files, such as __init__.py, these files are executed automatically upon import, leading to remote code execution. This issue can result in full system compromise, including file system access, network access, and potential persistence mechanisms.","status":"published","published":"2026-02-18T18:30:40Z","modified":"2026-06-06T14:46:20Z","cvss":[{"version":"3.0","score":10,"vector":"CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H","level":"critical"}],"cwes":["CWE-94"],"updated_at":"2026-11-02T14:40:18.682012Z"}],"nvd":[{"id":"CVE-2025-14009","description":"A critical vulnerability exists in the NLTK downloader component of nltk/nltk, affecting all versions. The _unzip_iter function in nltk/downloader.py uses zipfile.extractall() without performing path validation or security checks. This allows attackers to craft malicious zip packages that, when downloaded and extracted by NLTK, can execute arbitrary code. The vulnerability arises because NLTK assumes all downloaded packages are trusted and extracts them without validation. If a malicious package contains Python files, such as __init__.py, these files are executed automatically upon import, leading to remote code execution. This issue can result in full system compromise, including file system access, network access, and potential persistence mechanisms.","status":"published","published":"2026-02-18T18:24:19.41Z","modified":"2026-07-15T02:17:16.703Z","cvss":[{"version":"3.1","score":8.8,"vector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H","level":"high","assessor":"secondary"},{"version":"3.0","score":10,"vector":"CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H","level":"critical","assessor":"secondary"}],"cwes":["CWE-94"],"updated_at":"2026-11-02T14:12:00.273026Z"}],"osv":[{"id":"ALPINE-CVE-2025-14009","description":"A critical vulnerability exists in the NLTK downloader component of nltk/nltk, affecting all versions. The _unzip_iter function in nltk/downloader.py uses zipfile.extractall() without performing path validation or security checks. This allows attackers to craft malicious zip packages that, when downloaded and extracted by NLTK, can execute arbitrary code. The vulnerability arises because NLTK assumes all downloaded packages are trusted and extracts them without validation. If a malicious package contains Python files, such as __init__.py, these files are executed automatically upon import, leading to remote code execution. This issue can result in full system compromise, including file system access, network access, and potential persistence mechanisms.","status":"published","published":"2026-02-18T18:24:19.41Z","modified":"2026-11-03T06:33:00.309448247Z","cvss":[{"version":"3.1","score":8.8,"vector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H","level":"high"}],"updated_at":"2026-11-03T07:16:09.603409Z"},{"id":"CVE-2025-14009","title":"Zip Slip Vulnerability in nltk/nltk Leading to Remote Code Execution","description":"A critical vulnerability exists in the NLTK downloader component of nltk/nltk, affecting all versions. The _unzip_iter function in nltk/downloader.py uses zipfile.extractall() without performing path validation or security checks. This allows attackers to craft malicious zip packages that, when downloaded and extracted by NLTK, can execute arbitrary code. The vulnerability arises because NLTK assumes all downloaded packages are trusted and extracts them without validation. If a malicious package contains Python files, such as __init__.py, these files are executed automatically upon import, leading to remote code execution. This issue can result in full system compromise, including file system access, network access, and potential persistence mechanisms.","status":"published","published":"2026-02-18T17:45:17.573Z","modified":"2026-10-28T02:30:31.679245827Z","cvss":[{"version":"3.1","score":8.8,"vector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H","level":"high"}],"cwes":["CWE-94"],"updated_at":"2026-11-02T15:44:46.340268Z"},{"id":"DEBIAN-CVE-2025-14009","description":"A critical vulnerability exists in the NLTK downloader component of nltk/nltk, affecting all versions. The _unzip_iter function in nltk/downloader.py uses zipfile.extractall() without performing path validation or security checks. This allows attackers to craft malicious zip packages that, when downloaded and extracted by NLTK, can execute arbitrary code. The vulnerability arises because NLTK assumes all downloaded packages are trusted and extracts them without validation. If a malicious package contains Python files, such as __init__.py, these files are executed automatically upon import, leading to remote code execution. This issue can result in full system compromise, including file system access, network access, and potential persistence mechanisms.","status":"published","published":"2026-02-18T18:24:19.41Z","modified":"2026-09-01T20:04:12.362633212Z","cvss":[{"version":"3.1","score":8.8,"vector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H","level":"high"}],"updated_at":"2026-11-02T15:45:45.102284Z"},{"id":"GHSA-7p94-766c-hgjp","title":"NLTK has a Zip Slip Vulnerability","description":"A critical vulnerability exists in the NLTK downloader component of nltk/nltk, affecting all versions. The _unzip_iter function in nltk/downloader.py uses zipfile.extractall() without performing path validation or security checks. This allows attackers to craft malicious zip packages that, when downloaded and extracted by NLTK, can execute arbitrary code. The vulnerability arises because NLTK assumes all downloaded packages are trusted and extracts them without validation. If a malicious package contains Python files, such as __init__.py, these files are executed automatically upon import, leading to remote code execution. This issue can result in full system compromise, including file system access, network access, and potential persistence mechanisms.","status":"published","published":"2026-02-18T18:30:40Z","modified":"2026-09-10T03:50:34.416389229Z","cvss":[{"version":"3.0","score":10,"vector":"CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H","level":"critical"}],"cwes":["CWE-94"],"updated_at":"2026-11-02T15:46:41.349637Z"},{"id":"PYSEC-2026-96","description":"A critical vulnerability exists in the NLTK downloader component of nltk/nltk, affecting all versions. The _unzip_iter function in nltk/downloader.py uses zipfile.extractall() without performing path validation or security checks. This allows attackers to craft malicious zip packages that, when downloaded and extracted by NLTK, can execute arbitrary code. The vulnerability arises because NLTK assumes all downloaded packages are trusted and extracts them without validation. If a malicious package contains Python files, such as __init__.py, these files are executed automatically upon import, leading to remote code execution. This issue can result in full system compromise, including file system access, network access, and potential persistence mechanisms.","status":"published","published":"2026-02-18T18:24:19.41Z","modified":"2026-06-10T17:02:23.646726882Z","cvss":[{"version":"3.0","score":10,"vector":"CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H","level":"critical"}],"updated_at":"2026-11-02T15:52:58.117212Z"},{"id":"ROOT-APP-PYPI-CVE-2025-14009","title":"CVE-2025-14009 in nltk - Patched by Root","description":"Root has patched CVE-2025-14009 in the nltk package for Root:PyPI. Multiple fixed versions available.","status":"published","published":"2026-08-05T08:19:58Z","modified":"2026-08-09T23:00:05.992297948Z","cvss":[{"version":"3.0","score":10,"vector":"CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H","level":"critical"}],"updated_at":"2026-11-02T15:53:27.940619Z"},{"id":"UBUNTU-CVE-2025-14009","description":"A critical vulnerability exists in the NLTK downloader component of nltk/nltk, affecting all versions. The _unzip_iter function in nltk/downloader.py uses zipfile.extractall() without performing path validation or security checks. This allows attackers to craft malicious zip packages that, when downloaded and extracted by NLTK, can execute arbitrary code. The vulnerability arises because NLTK assumes all downloaded packages are trusted and extracts them without validation. If a malicious package contains Python files, such as __init__.py, these files are executed automatically upon import, leading to remote code execution. This issue can result in full system compromise, including file system access, network access, and potential persistence mechanisms.","status":"published","published":"2026-02-18T18:24:00Z","modified":"2026-10-17T12:56:48.044091535Z","cvss":[{"version":"3.0","score":10,"vector":"CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H","level":"critical"},{"version":"3.1","score":8.8,"vector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H","level":"high"}],"updated_at":"2026-11-02T16:55:20.144818Z"},{"id":"openSUSE-SU-2026:10226-1","title":"python311-nltk-3.9.1-3.1 on GA media","description":"These are all security issues fixed in the python311-nltk-3.9.1-3.1 package on the GA media of openSUSE Tumbleweed.","status":"published","published":"2026-02-19T00:00:00Z","modified":"2026-03-23T04:54:35.389162Z","updated_at":"2026-11-02T16:58:38.101535Z"},{"id":"USN-8214-1","title":"nltk vulnerability","description":"It was discovered that NLTK incorrectly handled file extraction when\nopening a maliciously crafted zip file. An attacker could possibly use this\nissue to create or overwrite files on the system and execute arbitrary\ncode.","status":"published","published":"2026-04-28T08:10:41Z","modified":"2026-06-30T18:15:54.978713552Z","updated_at":"2026-11-02T16:58:22.951676Z"}]}}