{"id":"CVE-2026-76875","summary":"PyPy pyexpat ExternalEntityParserCreate Use-After-Free","details":"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.","modified":"2026-10-04T02:30:50.149963611Z","published":"2026-09-29T12:45:19.797Z","database_specific":{"unresolved_ranges":[{"source":"AFFECTED_FIELD","extracted_events":[{"fixed":"3.11.16"},{"introduced":"3.12.0"},{"fixed":"3.12.14"}]}],"cna_assigner":"VulnCheck","cwe_ids":["CWE-416"],"osv_generated_from":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/76xxx/CVE-2026-76875.json"},"references":[{"type":"ADVISORY","url":"https://doc.pypy.org/release-v8.0.0.html"},{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/76xxx/CVE-2026-76875.json"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-76875"},{"type":"ADVISORY","url":"https://www.vulncheck.com/advisories/pypy-pyexpat-externalentityparsercreate-use-after-free"},{"type":"FIX","url":"https://github.com/pypy/pypy/releases/tag/release-pypy3.11-v8.0.0"},{"type":"FIX","url":"https://github.com/pypy/pypy/releases/tag/release-pypy3.12-v8.0.0"},{"type":"PACKAGE","url":"https://github.com/pypy/pypy"}],"affected":[{"ranges":[{"type":"GIT","repo":"https://github.com/pypy/pypy","events":[{"introduced":"0"},{"fixed":"78565394c9b55004add6156e0cc6d32eaf63dcc8"},{"fixed":"e778e9989a677fe281a9e2ae3447e213afcc875c"}],"database_specific":{"source":"REFERENCES"}}],"versions":["release-1.5"],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-76875.json"}}],"schema_version":"1.9.0","severity":[{"type":"CVSS_V4","score":"CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N"}]}