py-pdf/pypdf · Security
pypdf: Possible long runtimes for large xref table header limits
- GHSA ID
- GHSA-gmh7-3g9r-mjh5
- CVE ID
- CVE-2026-115580
- Severity
- high
- Published
- Updated
- CVSS v4
- 7.1 · 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
Description
Impact
An attacker who uses this vulnerability can craft a PDF which leads to long runtimes. This requires opening a file with large/wrong upper limits in the xref table.
Patches
This has been fixed in pypdf==6.21.2.
Workarounds
If you cannot upgrade yet, consider applying the changes from PR #4239.
CWEs
- CWE-834 · Excessive Iteration
References
- https://github.com/py-pdf/pypdf/security/advisories/GHSA-gmh7-3g9r-mjh5 ↗
- https://github.com/py-pdf/pypdf/pull/4239 ↗
- https://github.com/py-pdf/pypdf/commit/a3061e34b169d34478d520f5f049c53cfb1482b2 ↗
- https://github.com/py-pdf/pypdf/releases/tag/6.21.2 ↗
- https://github.com/advisories/GHSA-gmh7-3g9r-mjh5 ↗