{"id":"CVE-2026-59937","aliases":["GHSA-55h5-xmcq-c37v","PYSEC-2026-3610"],"title":"pypdf: Possible long runtimes for repeated malformed cross-reference entries ","summary":"pypdf: Possible long runtimes for repeated malformed cross-reference entries ","severity":"medium","vendor":"pypdf","product":"pypdf","ecosystem":"pip","affected":["pypdf < 6.14.0"],"patched":["pypdf 6.14.0"],"published":"2026-07-23","updated":"2026-09-10","sourceUpdated":"2026-09-10T03:50:12.272620075Z","source":"OSV","sourceUrl":"https://osv.dev/vulnerability/GHSA-55h5-xmcq-c37v","references":[{"url":"https://github.com/py-pdf/pypdf/security/advisories/GHSA-55h5-xmcq-c37v"},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-59937"},{"url":"https://github.com/py-pdf/pypdf/pull/3887"},{"url":"https://github.com/py-pdf/pypdf/commit/b5fc5aa714f4b696fb9b1deaa35a9e4a4eb50dae"},{"url":"https://github.com/py-pdf/pypdf"},{"url":"https://github.com/py-pdf/pypdf/releases/tag/6.14.0"},{"url":"https://github.com/advisories/GHSA-55h5-xmcq-c37v"}],"tags":["osv","pip","ghsa"],"epss":0.0062,"epssPercentile":0.47396,"cwe":["CWE-400"],"ingestedAt":"2026-07-23T15:18:37.923Z","slug":"CVE-2026-59937","body":"## Overview\n\n### Impact\n\nAn attacker who uses this vulnerability can craft a PDF which leads to long runtimes. This requires cross-reference streams with repeated malformed cross-reference streams.\n\n### Patches\n\nThis has been fixed in [pypdf==6.14.0](https://github.com/py-pdf/pypdf/releases/tag/6.14.0).\n\n### Workarounds\n\nIf you cannot upgrade yet, consider applying the changes from PR [#3887](https://github.com/py-pdf/pypdf/pull/3887).\n\n## Affected packages\n\n- `pypdf < 6.14.0`\n\n## Remediation\n\nUpgrade to a patched release:\n\n- `pypdf 6.14.0`","depth":"sunlit","depthScore":28,"depthScoreParts":{"impact":27.5,"likelihood":0.1,"exploitation":0,"ransomware":0},"changes":[]}