{"id":"CVE-2023-23931","aliases":["GHSA-w7pp-m8wf-vj6r","PYSEC-2023-11"],"url":"https://o3.security/vulnerability/CVE-2023-23931","summary":"Cipher.update_into can corrupt memory in pyca cryptography","details":"cryptography is a package designed to expose cryptographic primitives and recipes to Python developers. In affected versions `Cipher.update_into` would accept Python objects which implement the buffer protocol, but provide only immutable buffers. This would allow immutable objects (such as `bytes`) to be mutated, thus violating fundamental rules of Python and resulting in corrupted output. This now correctly raises an exception. This issue has been present since `update_into` was originally introduced in cryptography 1.8.","published":"2023-02-07T20:54:03.628Z","modified":"2026-08-12T03:51:09.020232532Z","cvss":{"score":4.8,"severity":"MEDIUM","vector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:L/A:L"},"epss":{"score":0.01301,"percentile":0.67827,"asOf":"2026-08-23"},"cisaKev":null,"exploitsKnown":1,"affectedPackages":[{"ecosystem":"PyPI","name":"cryptography","fixedVersion":"39.0.1"}],"fix":{"url":"https://github.com/pyca/cryptography/pull/8230/commits/94a50a9731f35405f0357fa5f3b177d46a726ab3","label":"pyca/cryptography#8230"},"references":[{"type":"WEB","url":"https://github.com/pyca/cryptography/pull/8230/commits/94a50a9731f35405f0357fa5f3b177d46a726ab3"},{"type":"WEB","url":"https://lists.debian.org/debian-lts-announce/2024/10/msg00012.html"},{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2023/23xxx/CVE-2023-23931.json"},{"type":"ADVISORY","url":"https://github.com/pyca/cryptography/security/advisories/GHSA-w7pp-m8wf-vj6r"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2023-23931"},{"type":"ADVISORY","url":"https://security.netapp.com/advisory/ntap-20230324-0007/"}],"provenance":{"sources":["OSV.dev","FIRST.org (EPSS)"],"lastVerified":"2026-08-12T03:51:09.020232532Z"}}