Fluid Attacks Database

Description

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

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.

Mitigation

Update Impact

Minimal update. May introduce new vulnerabilities or breaking changes.

Ecosystem	Component	Affected version	Patched versions
debian 12	pypdf	=3.17.4-1 \|\| =3.4.1-1 \|\| =3.4.1-1+deb12u1 \|\| =4.0.0-1 \|\| =4.0.0-1~exp1 \|\| =4.0.1-1 \|\| =4.0.2-1 \|\| =4.1.0-1 \|\| =4.2.0-1 \|\| =4.3.1-1 \|\| =5.4.0-1 \|\| =6.9.0-1 \|\| =6.9.2-1 \|\| =6.9.2-2	-
debian 13	pypdf	=5.4.0-1 \|\| =6.9.0-1 \|\| =6.9.2-1 \|\| =6.9.2-2	-
debian 14	pypdf	=5.4.0-1 \|\| =6.9.0-1 \|\| =6.9.2-1 \|\| =6.9.2-2	-
debian 11	pypdf2	=1.26.0-4 \|\| =1.26.0-4+deb11u1 \|\| =1.27.12-1 \|\| =1.27.9-1 \|\| =2.0.0-1 \|\| =2.10.0-1 \|\| =2.10.2-1 \|\| =2.10.3-1 \|\| =2.10.4-1 \|\| =2.10.5-1 \|\| =2.10.7-1 \|\| =2.10.9-1 \|\| =2.11.0-1 \|\| =2.11.1-1 \|\| =2.11.2-1 \|\| =2.12.1-1 \|\| =2.12.1-2 \|\| =2.12.1-3 \|\| =2.12.1-4 \|\| =2.4.1-1 \|\| =2.4.2-1 \|\| =2.6.0-1 \|\| =2.8.1-1 \|\| =2.9.0-1	-
debian 12	pypdf2	=2.12.1-3 \|\| =2.12.1-3+deb12u1 \|\| =2.12.1-4	-
pypi	pypdf	>=0 <6.14.0	6.14.0

Aliases

1. CVE-2026-599372. NVD-2026-599373. OSV-DEBIAN-2026-599374. OSV-2026-599375. GHSA-55h5-xmcq-c37v6. GCVE-2026-599377. SECURITY-TRACKER-CVE-2026-59937

References

1. https://github.com/py-pdf/pypdf/security/advisories/GHSA-55h5-xmcq-c37v2. https://github.com/py-pdf/pypdf/pull/38873. https://github.com/py-pdf/pypdf/commit/b5fc5aa714f4b696fb9b1deaa35a9e4a4eb50dae4. https://github.com/py-pdf/pypdf/releases/tag/6.14.0

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