{"id":"CVE-2026-22691","aliases":["GHSA-4f6g-68pf-7vhv","PYSEC-2026-1828"],"url":"https://o3.security/vulnerability/CVE-2026-22691","summary":"pypdf has possible long runtimes for malformed startxref","details":"pypdf is a free and open-source pure-python PDF library. Prior to version 6.6.0, pypdf has possible long runtimes for malformed startxref. An attacker who uses this vulnerability can craft a PDF which leads to possibly long runtimes for invalid startxref entries. When rebuilding the cross-reference table, PDF files with lots of whitespace characters become problematic. Only the non-strict reading mode is affected. Only the non-strict reading mode is affected. This issue has been patched in version 6.6.0.","published":"2026-01-10T04:46:12.423Z","modified":"2026-08-12T03:51:44.570249760Z","cvss":null,"epss":null,"cisaKev":null,"exploitsKnown":0,"affectedPackages":[{"ecosystem":"PyPI","name":"pypdf","fixedVersion":"6.6.0"}],"fix":{"url":"https://github.com/py-pdf/pypdf/commit/294165726b646bb7799be1cc787f593f2fdbcf45","label":"py-pdf/pypdf@2941657"},"references":[{"type":"WEB","url":"https://github.com/py-pdf/pypdf/releases/tag/6.6.0"},{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/22xxx/CVE-2026-22691.json"},{"type":"ADVISORY","url":"https://github.com/py-pdf/pypdf/security/advisories/GHSA-4f6g-68pf-7vhv"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-22691"},{"type":"FIX","url":"https://github.com/py-pdf/pypdf/commit/294165726b646bb7799be1cc787f593f2fdbcf45"},{"type":"FIX","url":"https://github.com/py-pdf/pypdf/pull/3594"}],"provenance":{"sources":["OSV.dev","FIRST.org (EPSS)"],"lastVerified":"2026-08-12T03:51:44.570249760Z"}}