{"schema_version":"1.9.0","id":"GHSA-55x5-fj6c-h6m8","published":"2021-12-13T18:14:36Z","modified":"2026-07-08T06:28:08.789724998Z","aliases":["CVE-2021-43818","PYSEC-2021-852"],"summary":"lxml's HTML Cleaner allows crafted and SVG embedded scripts to pass through","details":"### Impact\nThe HTML Cleaner in lxml.html lets certain crafted script content pass through, as well as script content in SVG files embedded using data URIs.\n\nUsers that employ the HTML cleaner in a security relevant context should upgrade to lxml 4.6.5.\n\n### Patches\nThe issue has been resolved in lxml 4.6.5.\n\n### Workarounds\nNone.\n\n### References\nThe issues are tracked under the report IDs GHSL-2021-1037 and GHSL-2021-1038.\n","affected":[{"package":{"name":"lxml","ecosystem":"PyPI","purl":"pkg:pypi/lxml"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"4.6.5"}]}],"versions":["1.3.2","1.3.3","1.3.4","1.3.5","1.3.6","2.0","2.0.10","2.0.11","2.0.4","2.0.5","2.0.6","2.0.7","2.0.8","2.0.9","2.1","2.1.1","2.1.2","2.1.3","2.1.4","2.1.5","2.2","2.2.1","2.2.2","2.2.3","2.2.4","2.2.5","2.2.6","2.2.7","2.2.8","2.3","2.3.1","2.3.2","2.3.3","2.3.4","2.3.5","2.3.6","3.0","3.0.2","3.1.0","3.1.1","3.1.2","3.2.0","3.2.1","3.2.2","3.2.3","3.2.4","3.2.5","3.3.0","3.3.1","3.3.2","3.3.3","3.3.4","3.3.5","3.3.6","3.4.0","3.4.1","3.4.2","3.4.3","3.4.4","3.5.0","3.6.0","3.6.1","3.6.2","3.6.3","3.6.4","3.7.0","3.7.1","3.7.2","3.7.3","3.8.0","4.0.0","4.1.0","4.1.1","4.2.0","4.2.1","4.2.2","4.2.3","4.2.4","4.2.5","4.2.6","4.3.0","4.3.2","4.3.3","4.3.4","4.3.5","4.4.0","4.4.1","4.4.2","4.4.3","4.5.0","4.5.1","4.5.2","4.6.0","4.6.1","4.6.2","4.6.3","4.6.4"],"database_specific":{"source":"https://github.com/github/advisory-database/blob/main/advisories/github-reviewed/2021/12/GHSA-55x5-fj6c-h6m8/GHSA-55x5-fj6c-h6m8.json"}}],"references":[{"type":"WEB","url":"https://github.com/lxml/lxml/security/advisories/GHSA-55x5-fj6c-h6m8"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2021-43818"},{"type":"WEB","url":"https://github.com/lxml/lxml/commit/12fa9669007180a7bb87d990c375cf91ca5b664a"},{"type":"WEB","url":"https://github.com/lxml/lxml/commit/a3eacbc0dcf1de1c822ec29fb7d090a4b1712a9c#diff-59130575b4fb2932c957db2922977d7d89afb0b2085357db1a14615a2fcad776"},{"type":"WEB","url":"https://github.com/lxml/lxml/commit/f2330237440df7e8f39c3ad1b1aa8852be3b27c0"},{"type":"WEB","url":"https://www.oracle.com/security-alerts/cpujul2022.html"},{"type":"WEB","url":"https://www.oracle.com/security-alerts/cpuapr2022.html"},{"type":"WEB","url":"https://www.debian.org/security/2022/dsa-5043"},{"type":"WEB","url":"https://security.netapp.com/advisory/ntap-20220107-0005"},{"type":"WEB","url":"https://security.gentoo.org/glsa/202208-06"},{"type":"WEB","url":"https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/ZQ4SPKJX3RRJK4UWA6FXCRHD2TVRQI44"},{"type":"WEB","url":"https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/WZGNET2A4WGLSUXLBFYKNC5PXHQMI3I7"},{"type":"WEB","url":"https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/V2XMOM5PFT6U5AAXY6EFNT5JZCKKHK2V"},{"type":"WEB","url":"https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/TUIS2KE3HZ2AAQKXFLTJFZPP2IFHJTC7"},{"type":"WEB","url":"https://lists.debian.org/debian-lts-announce/2021/12/msg00037.html"},{"type":"WEB","url":"https://github.com/pypa/advisory-database/tree/main/vulns/lxml/PYSEC-2021-852.yaml"},{"type":"PACKAGE","url":"https://github.com/lxml/lxml"}],"database_specific":{"cwe_ids":["CWE-74","CWE-79"],"github_reviewed":true,"github_reviewed_at":"2021-12-13T18:12:54Z","nvd_published_at":"2021-12-13T18:15:00Z","severity":"MODERATE"},"severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:H/A:N"},{"type":"CVSS_V4","score":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:N/VI:N/VA:N/SC:L/SI:H/SA:N"}]}