{"schemaVersion":3,"id":"CVE-2026-22691","aliases":["GHSA-4f6g-68pf-7vhv","PYSEC-2026-1828","UBUNTU-CVE-2026-22691","DEBIAN-CVE-2026-22691"],"status":"published","duplicateOf":null,"title":null,"description":"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. 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