CVE-2021-43818
HTML Cleaner allows crafted and SVG embedded scripts to pass through
HIGH 8.2
At a glance
- Source
- NVD
- EPSS
- EPSS 2.66 % · percentile 86 ()
- State
- PUBLISHED
- Published
- Updated
- Assigner
- GitHub_M
- NVD status
- Modified
Description
lxml is a library for processing XML and HTML in the Python language. Prior to version 4.6.5, the HTML Cleaner in lxml.html lets certain crafted script content pass through, as well as script content in SVG files embedded using data URIs. Users that employ the HTML cleaner in a security relevant context should upgrade to lxml 4.6.5 to receive a patch. There are no known workarounds available.
Weaknesses (CWE)
- CWE-74 — Improper Neutralization of Special Elements in Output Used by a Downstream Component
- CWE-79 — Improper Neutralization of Input During Web Page Generation
References
- https://github.com/lxml/lxml/security/advisories/GHSA-55x5-fj6c-h6m8
- https://github.com/lxml/lxml/commit/12fa9669007180a7bb87d990c375cf91ca5b664a
- https://github.com/lxml/lxml/commit/a3eacbc0dcf1de1c822ec29fb7d090a4b1712a9c#diff-59130575b4fb2932c957db2922977d7d89afb0b2085357db1a14615a2fcad776
- https://github.com/lxml/lxml/commit/f2330237440df7e8f39c3ad1b1aa8852be3b27c0
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/ZQ4SPKJX3RRJK4UWA6FXCRHD2TVRQI44/
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/WZGNET2A4WGLSUXLBFYKNC5PXHQMI3I7/
- https://lists.debian.org/debian-lts-announce/2021/12/msg00037.html
- https://www.debian.org/security/2022/dsa-5043
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/TUIS2KE3HZ2AAQKXFLTJFZPP2IFHJTC7/
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/V2XMOM5PFT6U5AAXY6EFNT5JZCKKHK2V/
- https://www.oracle.com/security-alerts/cpuapr2022.html
- https://security.netapp.com/advisory/ntap-20220107-0005/
- https://www.oracle.com/security-alerts/cpujul2022.html
- https://security.gentoo.org/glsa/202208-06
Scores
| Version | Score | Vector | Scored by |
|---|---|---|---|
| CVSS 3.1 | HIGH 8.2 | CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:H/A:N | GitHub_M |
| CVSS 3.1 | HIGH 8.2 | CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:H/A:N | NVD · security-advisories@github.com (Secondary) |
| CVSS 3.1 | HIGH 7.1 | CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:L | NVD · nvd@nist.gov (Primary) |
| CVSS 2.0 | MEDIUM 6.8 | AV:N/AC:M/Au:N/C:P/I:P/A:P | NVD · nvd@nist.gov (Primary) |
Advisories
- GHSA-55x5-fj6c-h6m8 — lxml's HTML Cleaner allows crafted and SVG embedded scripts to pass through
- PYSEC-2021-852 — lxml is a library for processing XML and HTML in the Python language. Prior to version 4.6.5, the HTML Cleaner in lxml.html lets certain crafted script content
European references
- ENISA EUVD · EUVD-2021-0117
- GCVE · GCVE-0-2021-43818
CERT-FR advisories
- CERTFR-2026-AVI-0395 — Multiples vulnérabilités dans les produits IBM · cert.ssi.gouv.fr
- CERTFR-2024-AVI-0506 — Multiples vulnérabilités dans Juniper Secure Analytics · cert.ssi.gouv.fr
- CERTFR-2024-AVI-0385 — Multiples vulnérabilités dans les produits IBM · cert.ssi.gouv.fr
- CERTFR-2024-AVI-0262 — Multiples vulnérabilités dans les produits IBM · cert.ssi.gouv.fr
Affected configurations (NVD CPE)
cpe:2.3:a:lxml:lxml:*:*:*:*:*:*:*:*< 4.6.5cpe:2.3:o:fedoraproject:fedora:34:*:*:*:*:*:*:*cpe:2.3:o:fedoraproject:fedora:35:*:*:*:*:*:*:*cpe:2.3:o:debian:debian_linux:9.0:*:*:*:*:*:*:*cpe:2.3:o:debian:debian_linux:10.0:*:*:*:*:*:*:*cpe:2.3:o:debian:debian_linux:11.0:*:*:*:*:*:*:*cpe:2.3:a:netapp:solidfire:-:*:*:*:*:*:*:*cpe:2.3:a:netapp:solidfire_enterprise_sds:-:*:*:*:*:*:*:*cpe:2.3:o:netapp:hci_storage_node_firmware:-:*:*:*:*:*:*:*cpe:2.3:a:oracle:communications_cloud_native_core_binding_support_function:22.1.3:*:*:*:*:*:*:*cpe:2.3:a:oracle:communications_cloud_native_core_network_exposure_function:22.1.1:*:*:*:*:*:*:*cpe:2.3:a:oracle:communications_cloud_native_core_policy:22.2.0:*:*:*:*:*:*:*cpe:2.3:a:oracle:http_server:12.2.1.3.0:*:*:*:*:*:*:*cpe:2.3:a:oracle:http_server:12.2.1.4.0:*:*:*:*:*:*:*cpe:2.3:a:oracle:zfs_storage_appliance_kit:8.8:*:*:*:*:*:*:*
Affected products
| Product | Versions |
|---|---|
| lxml · lxml | affected < 4.6.5 |
Sources
| Source | Licence |
|---|---|
| CVE List (CVEProject cvelistV5) | CVE Program Terms of Use |
| EPSS (FIRST.org) | FIRST — attribution requested |
| ENISA EUVD | ENISA — reproduction authorised, source acknowledged |
| CERT-FR (ANSSI) | Licence Ouverte / Etalab 2.0 |
| NVD (NIST) via fkie-cad/nvd-json-data-feeds | Public domain — this product uses data from the NVD API but is not endorsed or certified by the NVD |