CVE-2026-76875
mediumPyPy before versions 3.11.16 and 3.12.14 contains a use-after-free vulnerability in the pyexpat module's ExternalEntityParserCreate function that allows attack…
PyPy before versions 3.11.16 and 3.12.14 contains a use-after-free vulnerability in the pyexpat module's ExternalEntityParserCreate function that allows attackers to corrupt memory by supplying a crafted XML document to applications that create external-entity sub-parsers without retaining a reference to the parent parser. The child parser retains a raw C back-pointer to the parent parser struct while PyPy's tracing garbage collector can free the parent's C struct, causing bundled libexpat to dereference the freed pointer on every parsed token, producing memory corruption.
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N Affected products
Not reported by the source (unknown — not "none").
Weakness classification (CWE)
Source: NVD / CISA. “NVD-CWE-Other” and “NVD-CWE-noinfo” mean NVD could not assign a specific weakness.
Mitigation & advisories
No vendor advisory or patch reference tagged by NVD. Check the references below.
References
- https://doc.pypy.org/release-v8.0.0.html disclosure@vulncheck.com
- https://github.com/pypy/pypy/releases/tag/release-pypy3.11-v8.0.0 disclosure@vulncheck.com
- https://github.com/pypy/pypy/releases/tag/release-pypy3.12-v8.0.0 disclosure@vulncheck.com
- https://www.vulncheck.com/advisories/pypy-pyexpat-externalentityparsercreate-use-after-fre... disclosure@vulncheck.com
