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.
History

Tue, 04 Nov 2025 16:30:00 +0000

Type Values Removed Values Added
References

cve-icon MITRE

Status: PUBLISHED

Assigner: @huntrdev

Published: 2022-07-05T09:00:12.000Z

Updated: 2025-11-04T16:09:31.952Z

Reserved: 2022-07-05T00:00:00.000Z

Link: CVE-2022-2309

cve-icon Vulnrichment

No data.

cve-icon NVD

Status : Modified

Published: 2022-07-05T10:15:08.763

Modified: 2025-11-04T16:15:49.557

Link: CVE-2022-2309

cve-icon Redhat

Severity : Moderate

Publid Date: 2022-07-05T00:00:00Z

Links: CVE-2022-2309 - Bugzilla