py-pdf/pypdf · Security
pypdf: Possible long runtimes for repeated malformed cross-reference entries
- GHSA ID
- GHSA-55h5-xmcq-c37v
- CVE ID
- CVE-2026-59937
- Severity
- medium
- Published
- Updated
- CVSS v4
- 6.9 · CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:L/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 cross-reference streams with repeated malformed cross-reference streams.
Patches
This has been fixed in pypdf==6.14.0.
Workarounds
If you cannot upgrade yet, consider applying the changes from PR #3887.
CWEs
- CWE-400 · Uncontrolled Resource Consumption
References
- https://github.com/py-pdf/pypdf/security/advisories/GHSA-55h5-xmcq-c37v ↗
- https://nvd.nist.gov/vuln/detail/CVE-2026-59937 ↗
- https://github.com/py-pdf/pypdf/pull/3887 ↗
- https://github.com/py-pdf/pypdf/commit/b5fc5aa714f4b696fb9b1deaa35a9e4a4eb50dae ↗
- https://github.com/py-pdf/pypdf/releases/tag/6.14.0 ↗
- https://github.com/advisories/GHSA-55h5-xmcq-c37v ↗