{"id":"CVE-2026-22691","title":"pypdf: pypdf: Denial of Service via malformed PDF startxref entries (CVE-2026-22691)","summary":"A flaw was found in pypdf. A remote attacker can exploit this vulnerability by crafting a malicious PDF file with malformed startxref entries and excessive whitespace characters. This can cause excessively long processing times when rebuil…","severity":"medium","cvss":6.5,"cvssVector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H","cvssSource":"vendor","cwe":"CWE-1050","vendor":"Red Hat","product":"Red Hat Ansible Automation Platform 2","affected":["openshift_lightspeed","ansible_automation_platform 2","enterprise_linux_ai_rhel_ai 3","openshift_ai_rhoai"],"patched":["pypdf 6.6.0"],"published":"2026-01-10","updated":"2026-10-15","sourceUpdated":"2026-10-15T11:33:26+00:00","source":"CSAF","sourceUrl":"https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-22691.json","references":[{"url":"https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-22691.json"},{"url":"https://access.redhat.com/security/cve/CVE-2026-22691"},{"url":"https://bugzilla.redhat.com/show_bug.cgi?id=2428427"},{"url":"https://www.cve.org/CVERecord?id=CVE-2026-22691"},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-22691"},{"url":"https://github.com/py-pdf/pypdf/commit/294165726b646bb7799be1cc787f593f2fdbcf45"},{"url":"https://github.com/py-pdf/pypdf/pull/3594"},{"url":"https://github.com/py-pdf/pypdf/releases/tag/6.6.0"},{"url":"https://github.com/py-pdf/pypdf/security/advisories/GHSA-4f6g-68pf-7vhv"},{"url":"https://github.com/py-pdf/pypdf"}],"tags":["csaf","vex","red-hat","osv","pip"],"epss":0.00433,"epssPercentile":0.37456,"aliases":["GHSA-4f6g-68pf-7vhv","PYSEC-2026-1828"],"ecosystem":"pip","ingestedAt":"2026-07-08T18:25:45.466Z","slug":"CVE-2026-22691","body":"## Overview\n\nA flaw was found in pypdf. A remote attacker can exploit this vulnerability by crafting a malicious PDF file with malformed startxref entries and excessive whitespace characters. This can cause excessively long processing times when rebuilding the cross-reference table in non-strict reading mode, leading to a denial of service.\n\n## Vendor advisories\n\n- **Red Hat VEX** · Moderate · affected: OpenShift Lightspeed, Red Hat Ansible Automation Platform 2, Red Hat Enterprise Linux AI (RHEL AI) 3, Red Hat OpenShift AI (RHOAI) · no fix planned: OpenShift Lightspeed, Red Hat Ansible Automation Platform 2, Red Hat Enterprise Linux AI (RHEL AI) 3, Red Hat OpenShift AI (RHOAI) · updated 2026-10-15 · [vex](https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-22691.json)\n\n**pypdf: pypdf: Denial of Service via malformed PDF startxref entries** — rated Moderate by Red Hat. Released 2026-01-10, updated 2026-10-15.\n\nAffected:\n\n- OpenShift Lightspeed\n- Red Hat Ansible Automation Platform 2\n- Red Hat Enterprise Linux AI (RHEL AI) 3\n- Red Hat OpenShift AI (RHOAI)\n\nNo fix planned:\n\n- OpenShift Lightspeed\n- Red Hat Ansible Automation Platform 2\n- Red Hat Enterprise Linux AI (RHEL AI) 3\n- Red Hat OpenShift AI (RHOAI)\n\n## Remediation\n\nFix deferred\n\n## Package advisory (CVE-2026-22691)\n\nAffected packages:\n\n- `pypdf < 6.6.0`\n\nPatched in:\n\n- `pypdf 6.6.0`\n\nSource: https://osv.dev/vulnerability/GHSA-4f6g-68pf-7vhv","depth":"sunlit","depthScore":36,"depthScoreParts":{"impact":35.8,"likelihood":0.1,"exploitation":0,"ransomware":0},"changes":[{"seq":222197,"id":"CVE-2026-22691","ts":1792065062939,"field":"cvss","old":null,"new":"6.5"},{"seq":222196,"id":"CVE-2026-22691","ts":1792065062939,"field":"severity","old":"low","new":"medium"}]}