CVE-2026-59937

Summary

pypdf: Possible long runtimes for repeated malformed cross-reference entries

Severity

medium

EPSS

0.6% (p49)

CWE

CWE-400

Also known as

GHSA-55h5-xmcq-c37v

Published

2026-07-23

Updated

2026-07-23

Advisory details

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.

References

• https://github.com/advisories/GHSA-55h5-xmcq-c37v
• 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

Related advisories

• CVE-2026-115572 — high · PyPI/pypdf
• CVE-2026-115585 — high · PyPI/pypdf
• CVE-2026-102999 — high · PyPI/pypdf
• CVE-2026-102998 — high · PyPI/pypdf
• CVE-2026-103000 — high · PyPI/pypdf
• CVE-2026-102997 — high · PyPI/pypdf
• CVE-2026-102996 — high · PyPI/pypdf
• CVE-2026-102995 — high · PyPI/pypdf

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