CVE-2022-2309
NULL Pointer Dereference in lxml/lxml
At a glance
- Severity
- MEDIUM 5.3
- EPSS
- EPSS 2.45 % · percentile 84 (2026-10-27)
- State
- PUBLISHED
- Published
- Updated
- Assigner
- @huntrdev
- NVD status
- Modified
Description
NULL Pointer Dereference allows attackers to cause a denial of service (or application crash). This only applies when lxml is used together with libxml2 2.9.10 through 2.9.14. libxml2 2.9.9 and earlier are not affected. It allows triggering crashes through forged input data, given a vulnerable code sequence in the application. The vulnerability is caused by the iterwalk function (also used by the canonicalize function). Such code shouldn't be in wide-spread use, given that parsing + iterwalk would usually be replaced with the more efficient iterparse function. However, an XML converter that serialises to C14N would also be vulnerable, for example, and there are legitimate use cases for this code sequence. If untrusted input is received (also remotely) and processed via iterwalk function, a crash can be triggered.
Scores
| Version | Score | Vector | Scored by |
|---|---|---|---|
| CVSS 3.0 | MEDIUM 5.3 | CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L | @huntrdev |
| CVSS 3.1 | HIGH 7.5 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H | NVD · nvd@nist.gov (Primary) |
| CVSS 3.0 | MEDIUM 5.3 | CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L | NVD · security@huntr.dev (Secondary) |
| CVSS 2.0 | MEDIUM 5.0 | AV:N/AC:L/Au:N/C:N/I:N/A:P | NVD · nvd@nist.gov (Primary) |
Weaknesses (CWE)
Advisories
- GHSA-wrxv-2j5q-m38w — lxml NULL Pointer Dereference allows attackers to cause a denial of service
- PYSEC-2022-230 — NULL Pointer Dereference allows attackers to cause a denial of service (or application crash). This only applies when lxml is used together with libxml2 2.9.10
European references
- ENISA EUVD · EUVD-2022-0148
- GCVE · GCVE-0-2022-2309
CERT-FR advisories
- CERTFR-2026-AVI-1385 — Multiples vulnérabilités dans les produits VMware · cert.ssi.gouv.fr
- CERTFR-2026-AVI-0287 — Multiples vulnérabilités dans les produits NetApp · cert.ssi.gouv.fr
- CERTFR-2026-AVI-0218 — Multiples vulnérabilités dans les produits VMware · cert.ssi.gouv.fr
- CERTFR-2025-AVI-1057 — Multiples vulnérabilités dans les produits VMware · cert.ssi.gouv.fr
- CERTFR-2025-AVI-0969 — Multiples vulnérabilités dans les produits VMware · cert.ssi.gouv.fr
- CERTFR-2025-AVI-0756 — Multiples vulnérabilités dans les produits VMware · cert.ssi.gouv.fr
- CERTFR-2025-AVI-0303 — Multiples vulnérabilités dans les produits Splunk · cert.ssi.gouv.fr
- CERTFR-2023-AVI-0701 — Multiples vulnérabilités dans Splunk · cert.ssi.gouv.fr
- CERTFR-2023-AVI-0197 — Multiples vulnérabilités dans VMware Spring · cert.ssi.gouv.fr
- CERTFR-2022-AVI-959 — Multiples vulnérabilités dans Tenable Nessus · cert.ssi.gouv.fr
- CERTFR-2022-AVI-1019 — Multiples vulnérabilités dans Tenable Nessus · cert.ssi.gouv.fr
Affected configurations (NVD CPE)
cpe:2.3:a:lxml:lxml:*:*:*:*:*:*:*:*< 4.9.1cpe:2.3:o:fedoraproject:fedora:36:*:*:*:*:*:*:*cpe:2.3:o:fedoraproject:fedora:37:*:*:*:*:*:*:*
Affected products
| Product | Versions |
|---|---|
| lxml · lxml/lxml | affected unspecified < 4.9.1 |
References
- https://huntr.dev/bounties/8264e74f-edda-4c40-9956-49de635105ba
- https://github.com/lxml/lxml/commit/86368e9cf70a0ad23cccd5ee32de847149af0c6f
- https://security.gentoo.org/glsa/202208-06
- https://security.netapp.com/advisory/ntap-20220915-0006/
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/URHHSIBTPTALXMECRLAC2EVDNAFSR5NO/
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/HGYC6L7ENH5VEGN3YWFBYMGKX6WNS7HZ/
- https://lists.debian.org/debian-lts-announce/2024/09/msg00021.html
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 |