{"id":"CVE-2026-22690","aliases":["GHSA-4xc4-762w-m6cg","PYSEC-2026-1829"],"title":"pypdf has possible long runtimes for missing /Root object with large /Size values","summary":"pypdf has possible long runtimes for missing /Root object with large /Size values","severity":"low","vendor":"pypdf","product":"pypdf","ecosystem":"pip","affected":["pypdf < 6.6.0"],"patched":["pypdf 6.6.0"],"published":"2026-01-09","updated":"2026-07-07","source":"OSV","sourceUrl":"https://osv.dev/vulnerability/GHSA-4xc4-762w-m6cg","references":[{"url":"https://github.com/py-pdf/pypdf/security/advisories/GHSA-4xc4-762w-m6cg"},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-22690"},{"url":"https://github.com/py-pdf/pypdf/pull/3594"},{"url":"https://github.com/py-pdf/pypdf/commit/294165726b646bb7799be1cc787f593f2fdbcf45"},{"url":"https://github.com/py-pdf/pypdf"},{"url":"https://github.com/py-pdf/pypdf/releases/tag/6.6.0"}],"tags":["osv","pip"],"epss":0.0044,"epssPercentile":0.37549,"ingestedAt":"2026-07-08T18:25:45.724Z","slug":"CVE-2026-22690","body":"## Overview\n\n### Impact\nAn attacker who exploits this vulnerability can craft a PDF which leads to possibly long runtimes for actually invalid files. This can be achieved by omitting the `/Root` entry in the trailer, while using a rather large `/Size` value. Only the non-strict reading mode is affected.\n\n### Patches\nThis has been fixed in [pypdf==6.6.0](https://github.com/py-pdf/pypdf/releases/tag/6.6.0).\n\n### Workarounds\n\n```python\nfrom pypdf import PdfReader, PdfWriter\n\n\n# Instead of\nreader = PdfReader(\"file.pdf\")\n# use the strict mode:\nreader = PdfReader(\"file.pdf\", strict=True)\n\n# Instead of\nwriter = PdfWriter(clone_from=\"file.pdf\")\n# use an explicit strict reader:\nwriter = PdfWriter(clone_from=PdfReader(\"file.pdf\", strict=True))\n```\n\n### Resources\nThis issue has been fixed in #3594.\n\n## Affected packages\n\n- `pypdf < 6.6.0`\n\n## Remediation\n\nUpgrade to a patched release:\n\n- `pypdf 6.6.0`","depth":"sunlit","depthScore":14,"depthScoreParts":{"impact":13.8,"likelihood":0.1,"exploitation":0,"ransomware":0},"changes":[]}