{"id":"CVE-2018-7753","aliases":["DEBIAN-CVE-2018-7753","EUVD-2018-0026","GHSA-m9mq-p2f9-cfqv","PYSEC-2018-51","UBUNTU-CVE-2018-7753","USN-8077-1","openSUSE-SU-2024:11219-1","openSUSE-SU-2024:14134-1","openSUSE-SU-2026:11323-1"],"status":"published","title":"Bleach URI Scheme Restriction Bypass","description":"An issue was discovered in Bleach 2.1.x before 2.1.3. Attributes that have URI values weren't properly sanitized if the values contained character entities. Using character entities, it was possible to construct a URI value with a scheme that was not allowed that would slide through unsanitized.","severity":{"version":"3.0","score":9.8,"vector":"CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H","level":"critical","assessor":"primary","from":"nvd"},"epss":{"day":"2026-11-07","score":0.02172,"percentile":0.824,"model":"v2026.06.15"},"facts":{"in_kev":false,"known_exploited":false,"public_exploit":false,"fix_available":true},"cwes":["CWE-20"],"published":"2018-03-07T23:00:00Z","modified":"2026-10-23T18:03:08Z","fixes":[{"ecosystem":"PyPI","package":"bleach","fixed_in":["2.1.3"],"sources":["ghsa","osv"]},{"ecosystem":"Debian:12","package":"python-bleach","fixed_in":["2.1.3-1"],"sources":["osv"]},{"ecosystem":"Debian:13","package":"python-bleach","fixed_in":["2.1.3-1"],"sources":["osv"]},{"ecosystem":"Debian:14","package":"python-bleach","fixed_in":["2.1.3-1"],"sources":["osv"]},{"ecosystem":"Ubuntu:Pro:18.04:LTS","package":"python-bleach","fixed_in":["2.1.2-1ubuntu0.1~esm1"],"sources":["osv"]},{"ecosystem":"Ubuntu:Pro:16.04:LTS","package":"python-bleach","fixed_in":["1.4.2-1ubuntu0.1~esm1"],"sources":["osv"]},{"ecosystem":"Ubuntu:Pro:20.04:LTS","package":"python-bleach","fixed_in":["3.1.1-1ubuntu0.1~esm1"],"sources":["osv"]}],"affected":[{"source":"ghsa","ecosystem":"PyPI","package":"bleach","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"2.1.0"},{"fixed":"2.1.3"}]}]},{"source":"osv","ecosystem":"Debian:12","package":"python-bleach","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"2.1.3-1"}]}]},{"source":"osv","ecosystem":"Debian:13","package":"python-bleach","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"2.1.3-1"}]}]},{"source":"osv","ecosystem":"Debian:14","package":"python-bleach","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"2.1.3-1"}]}]},{"source":"osv","ecosystem":"PyPI","package":"bleach","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"2.1.0"},{"fixed":"2.1.3"}]}],"versions":["2.1","2.1.1","2.1.2"]},{"source":"osv","ecosystem":"PyPI","package":"bleach","ranges":[{"type":"GIT","events":[{"introduced":"0"},{"fixed":"c5df5789ec3471a31311f42c2d19fc2cf21b35ef"}]},{"type":"ECOSYSTEM","events":[{"introduced":"2.1"},{"fixed":"2.1.3"}]}],"versions":["2.1","2.1.1","2.1.2"]},{"source":"osv","ecosystem":"Ubuntu:Pro:18.04:LTS","package":"python-bleach","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"2.1.2-1ubuntu0.1~esm1"}]}],"versions":["2.0-1","2.1.2-1"]},{"source":"osv","ecosystem":"Ubuntu:Pro:16.04:LTS","package":"python-bleach","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"1.4.2-1ubuntu0.1~esm1"}]}],"versions":["1.4-1","1.4.2-1"]},{"source":"osv","ecosystem":"Ubuntu:Pro:18.04:LTS","package":"python-bleach","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"2.1.2-1ubuntu0.1~esm1"}]}],"versions":["2.0-1","2.1.2-1"]},{"source":"osv","ecosystem":"Ubuntu:Pro:20.04:LTS","package":"python-bleach","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"3.1.1-1ubuntu0.1~esm1"}]}],"versions":["3.1.0-1","3.1.0-2","3.1.1-1"]},{"source":"osv","ecosystem":"openSUSE:Tumbleweed","package":"python-bleach","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"6.1.0-1.5"}]}],"bundled":5},{"source":"osv","ecosystem":"openSUSE:Tumbleweed","package":"python-bleach","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"6.4.0-1.1"}]}],"bundled":5}],"products":[{"vendor":"mozilla","product":"bleach"}],"references":[{"url":"https://github.com/mozilla/bleach/releases/tag/v2.1.3","tags":["x_refsource_MISC","x_transferred","Third Party Advisory","advisory","web","report"]},{"url":"https://github.com/mozilla/bleach/commit/c5df5789ec3471a31311f42c2d19fc2cf21b35ef","tags":["x_refsource_MISC","x_transferred","Patch","Third Party Advisory","fix","web","report"]},{"url":"https://bugs.debian.org/892252","tags":["x_refsource_MISC","x_transferred","Third Party Advisory","advisory","web","report"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2018-7753","tags":["advisory"]},{"url":"https://github.com/pypa/advisory-database/tree/main/vulns/bleach/PYSEC-2018-51.yaml","tags":["web"]},{"url":"https://github.com/advisories/GHSA-m9mq-p2f9-cfqv","tags":["advisory"]},{"url":"https://security-tracker.debian.org/tracker/CVE-2018-7753","tags":["advisory"]},{"url":"https://github.com/mozilla/bleach","tags":["package"]},{"url":"https://ubuntu.com/security/CVE-2018-7753","tags":["report"]},{"url":"https://github.com/mozilla/bleach/pull/356","tags":["report"]},{"url":"https://www.cve.org/CVERecord?id=CVE-2018-7753","tags":["report"]},{"url":"https://ubuntu.com/security/notices/USN-8077-1","tags":["advisory"]},{"url":"https://ubuntu.com/security/CVE-2020-6802","tags":["report"]},{"url":"https://ubuntu.com/security/CVE-2020-6816","tags":["report"]},{"url":"https://ubuntu.com/security/CVE-2020-6817","tags":["report"]},{"url":"https://ubuntu.com/security/CVE-2021-23980","tags":["report"]},{"url":"","tags":["advisory"]},{"url":"https://www.suse.com/security/cve/CVE-2018-7753","tags":["web"]},{"url":"https://www.suse.com/security/cve/CVE-2020-6802","tags":["web"]},{"url":"https://www.suse.com/security/cve/CVE-2020-6816","tags":["web"]},{"url":"https://www.suse.com/security/cve/CVE-2020-6817","tags":["web"]},{"url":"https://www.suse.com/security/cve/CVE-2021-23980","tags":["web"]}],"sources":{"cve":[{"id":"CVE-2018-7753","description":"An issue was discovered in Bleach 2.1.x before 2.1.3. Attributes that have URI values weren't properly sanitized if the values contained character entities. Using character entities, it was possible to construct a URI value with a scheme that was not allowed that would slide through unsanitized.","status":"published","published":"2018-03-07T23:00:00Z","modified":"2024-09-17T01:25:52.866Z","updated_at":"2026-11-02T14:35:10.313768Z"}],"euvd":[{"id":"EUVD-2018-0026","description":"An issue was discovered in Bleach 2.1.x before 2.1.3. Attributes that have URI values weren't properly sanitized if the values contained character entities. Using character entities, it was possible to construct a URI value with a scheme that was not allowed that would slide through unsanitized.","status":"published","published":"2018-03-07T23:00:00Z","modified":"2024-09-17T01:25:52Z","updated_at":"2026-11-03T00:28:49.824577Z"}],"ghsa":[{"id":"GHSA-m9mq-p2f9-cfqv","title":"Bleach URI Scheme Restriction Bypass","description":"An issue was discovered in Bleach 2.1.x before 2.1.3. Attributes that have URI values weren't properly sanitized if the values contained character entities. Using character entities, it was possible to construct a URI value with a scheme that was not allowed that would slide through unsanitized.","status":"published","published":"2019-01-04T17:46:30Z","modified":"2024-09-04T19:41:52Z","cvss":[{"version":"3.0","score":9.8,"vector":"CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H","level":"critical"},{"version":"4.0","score":9.3,"vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N","level":"critical"}],"cwes":["CWE-20"],"updated_at":"2026-11-02T14:38:01.080229Z"}],"nvd":[{"id":"CVE-2018-7753","description":"An issue was discovered in Bleach 2.1.x before 2.1.3. Attributes that have URI values weren't properly sanitized if the values contained character entities. Using character entities, it was possible to construct a URI value with a scheme that was not allowed that would slide through unsanitized.","status":"published","published":"2018-03-07T23:29:00.273Z","modified":"2026-06-17T02:03:39.29Z","cvss":[{"version":"3.0","score":9.8,"vector":"CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H","level":"critical","assessor":"primary"},{"version":"2.0","score":7.5,"vector":"AV:N/AC:L/Au:N/C:P/I:P/A:P","level":"high","assessor":"primary"}],"cwes":["CWE-20"],"updated_at":"2026-11-02T14:04:23.783914Z"}],"osv":[{"id":"CVE-2018-7753","description":"An issue was discovered in Bleach 2.1.x before 2.1.3. Attributes that have URI values weren't properly sanitized if the values contained character entities. Using character entities, it was possible to construct a URI value with a scheme that was not allowed that would slide through unsanitized.","status":"published","published":"2018-03-07T23:29:00.273Z","modified":"2026-10-20T10:50:31.147976453Z","cvss":[{"version":"3.0","score":9.8,"vector":"CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H","level":"critical"}],"updated_at":"2026-11-02T15:44:09.74357Z"},{"id":"DEBIAN-CVE-2018-7753","description":"An issue was discovered in Bleach 2.1.x before 2.1.3. Attributes that have URI values weren't properly sanitized if the values contained character entities. Using character entities, it was possible to construct a URI value with a scheme that was not allowed that would slide through unsanitized.","status":"published","published":"2018-03-07T23:29:00.273Z","modified":"2026-10-23T18:03:08.93733806Z","cvss":[{"version":"3.0","score":9.8,"vector":"CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H","level":"critical"}],"updated_at":"2026-11-02T15:45:31.170944Z"},{"id":"GHSA-m9mq-p2f9-cfqv","title":"Bleach URI Scheme Restriction Bypass","description":"An issue was discovered in Bleach 2.1.x before 2.1.3. Attributes that have URI values weren't properly sanitized if the values contained character entities. Using character entities, it was possible to construct a URI value with a scheme that was not allowed that would slide through unsanitized.","status":"published","published":"2019-01-04T17:46:30Z","modified":"2025-02-16T05:29:49.530342Z","cvss":[{"version":"3.0","score":9.8,"vector":"CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H","level":"critical"},{"version":"4.0","score":9.3,"vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N","level":"critical"}],"cwes":["CWE-20"],"updated_at":"2026-11-02T15:46:51.811331Z"},{"id":"UBUNTU-CVE-2018-7753","description":"An issue was discovered in Bleach 2.1.x before 2.1.3. Attributes that have URI values weren't properly sanitized if the values contained character entities. Using character entities, it was possible to construct a URI value with a scheme that was not allowed that would slide through unsanitized.","status":"published","published":"2018-03-07T23:29:00Z","modified":"2026-03-09T11:14:02.732852Z","cvss":[{"version":"3.0","score":9.8,"vector":"CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H","level":"critical"}],"updated_at":"2026-11-02T15:54:18.772093Z"},{"id":"openSUSE-SU-2024:11219-1","title":"python36-bleach-3.3.0-1.4 on GA media","description":"These are all security issues fixed in the python36-bleach-3.3.0-1.4 package on the GA media of openSUSE Tumbleweed.","status":"published","published":"2024-06-15T00:00:00Z","modified":"2026-02-04T04:41:03.69776Z","updated_at":"2026-11-02T16:58:34.894275Z"},{"id":"openSUSE-SU-2024:14134-1","title":"python310-bleach-6.1.0-1.5 on GA media","description":"These are all security issues fixed in the python310-bleach-6.1.0-1.5 package on the GA media of openSUSE Tumbleweed.","status":"published","published":"2024-07-12T00:00:00Z","modified":"2025-05-07T18:10:19.482546Z","updated_at":"2026-11-02T16:58:36.662953Z"},{"id":"openSUSE-SU-2026:11323-1","title":"python313-bleach-6.4.0-1.1 on GA media","description":"These are all security issues fixed in the python313-bleach-6.4.0-1.1 package on the GA media of openSUSE Tumbleweed.","status":"published","published":"2026-07-21T00:00:00Z","modified":"2026-07-22T09:30:06.046081622Z","updated_at":"2026-11-02T16:58:38.95195Z"},{"id":"PYSEC-2018-51","description":"An issue was discovered in Bleach 2.1.x before 2.1.3. Attributes that have URI values weren't properly sanitized if the values contained character entities. Using character entities, it was possible to construct a URI value with a scheme that was not allowed that would slide through unsanitized.","status":"published","published":"2018-03-07T23:29:00Z","modified":"2023-11-08T04:00:23.566004Z","updated_at":"2026-11-02T15:52:52.192131Z"},{"id":"USN-8077-1","title":"python-bleach vulnerabilities","description":"It was discovered that Bleach did not properly sanitize URI attributes\ncontaining character entities. An attacker could possibly use this issue\nto construct a URI with a disallowed scheme that would bypass\nsanitization, leading to cross-site scripting. This issue only affected\nUbuntu 18.04 LTS. (CVE-2018-7753)\n\nYaniv Nizry discovered that Bleach was vulnerable to a mutation\ncross-site scripting issue when sanitizing HTML with the noscript tag\nand a raw tag in the allowed tags list. An attacker could possibly\nuse this issue to inject malicious content, leading to cross-site\nscripting. This issue only affected Ubuntu 18.04 LTS. (CVE-2020-6802)\n\nYaniv Nizry discovered that Bleach was vulnerable to a mutation\ncross-site scripting issue when sanitizing HTML with RCDATA together\nwith svg or math tags in the allowed tags list. An attacker could\npossibly use this issue to inject malicious content, leading to\ncross-site scripting. (CVE-2020-6816)\n\nIt was discovered that Bleach incorrectly handled parsing of style\nattributes when sanitizing HTML. An attacker could possibly use this\nissue to perform a regular expression denial of service, leading to\nexcessive resource consumption. (CVE-2020-6817)\n\nYaniv Nizry and Michał Bentkowski discovered that Bleach was vulnerable\nto a mutation cross-site scripting issue when sanitizing HTML with\ncertain combinations of allowed tags. An attacker could possibly use\nthis issue to inject malicious content, leading to cross-site scripting.\n(CVE-2021-23980)","status":"published","published":"2026-03-05T16:04:13Z","modified":"2026-06-25T13:32:31.684046454Z","updated_at":"2026-11-02T16:58:22.951676Z"}]}}