{"id":"CVE-2026-115580","title":"pypdf: Possible long runtimes for large xref table header limits","summary":"pypdf is a free and open-source pure-python PDF library. Prior to 6.21.2, an attacker can craft a PDF with a standard cross-reference table whose declared entry count exceeds what the file can contain, causing excessive processing and lo…","severity":"high","cvss":7.1,"cvssVector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N","cvssSource":"cna","cwe":["CWE-834"],"vendor":"py-pdf","product":"pypdf","affected":["pypdf < 6.21.2"],"ssvc":{"exploitation":"none","automatable":"no","technicalImpact":"partial","timestamp":"2026-10-29T18:01:08.614500Z"},"published":"2026-10-23","updated":"2026-10-29","sourceUpdated":"2026-10-29T18:01:23.279Z","source":"CVEORG","sourceUrl":"https://www.cve.org/CVERecord?id=CVE-2026-115580","references":[{"url":"https://github.com/py-pdf/pypdf/security/advisories/GHSA-gmh7-3g9r-mjh5","label":"https://github.com/py-pdf/pypdf/security/advisories/GHSA-gmh7-3g9r-mjh5"},{"url":"https://github.com/py-pdf/pypdf/pull/4239","label":"https://github.com/py-pdf/pypdf/pull/4239"},{"url":"https://github.com/py-pdf/pypdf/commit/a3061e34b169d34478d520f5f049c53cfb1482b2","label":"https://github.com/py-pdf/pypdf/commit/a3061e34b169d34478d520f5f049c53cfb1482b2"},{"url":"https://github.com/py-pdf/pypdf/releases/tag/6.21.2","label":"https://github.com/py-pdf/pypdf/releases/tag/6.21.2"},{"url":"https://github.com/py-pdf/pypdf"},{"url":"https://github.com/advisories/GHSA-gmh7-3g9r-mjh5"}],"tags":["cve.org","osv","pip","ghsa"],"epss":0.0041,"epssPercentile":0.35246,"aliases":["GHSA-gmh7-3g9r-mjh5"],"ecosystem":"pip","patched":["pypdf 6.21.2"],"ingestedAt":"2026-10-23T20:36:51.540Z","slug":"CVE-2026-115580","body":"## Overview\n\npypdf is a free and open-source pure-python PDF library. Prior to 6.21.2, an attacker can craft a PDF with a standard cross-reference table whose declared entry count exceeds what the file can contain, causing excessive processing and long runtimes when the file is opened. This issue is fixed in version 6.21.2.\n\n## Affected\n\n- `pypdf < 6.21.2`\n\n## Remediation\n\nRefer to the linked advisories for vendor-supplied fixes and affected version ranges.\n\n## Package advisory (CVE-2026-115580)\n\nAffected packages:\n\n- `pypdf < 6.21.2`\n\nPatched in:\n\n- `pypdf 6.21.2`\n\nSource: https://osv.dev/vulnerability/GHSA-gmh7-3g9r-mjh5","depth":"twilight","depthScore":39,"depthScoreParts":{"impact":39.1,"likelihood":0.1,"exploitation":0,"ransomware":0},"changes":[]}