Fluid Attacks Database

Description

pypdf: Possible large memory usage when retrieving alphabetical page labels

Impact

An attacker who uses this vulnerability can craft a PDF which leads to large memory consumption. This requires accessing the page labels of a document with large alphabetical labels.

Patches

This has been fixed in pypdf==6.19.0.

Workarounds

If you cannot upgrade yet, consider applying the changes from PR #4096.

Mitigation

Update Impact

Minimal update. May introduce new vulnerabilities or breaking changes.

Ecosystem	Component	Affected version	Patched versions
pypi	pypdf	>=0 <6.19.0	6.19.0
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 \|\| =6.19.0-1 \|\| =6.9.0-1 \|\| =6.9.2-1 \|\| =6.9.2-2	-
debian 13	pypdf	=5.4.0-1 \|\| =6.19.0-1 \|\| =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 \|\| >=0 <6.19.0-1	6.19.0-1

Aliases

1. CVE-2026-1030002. NVD-2026-1030003. OSV-2026-1030004. OSV-DEBIAN-2026-1030005. GHSA-w23x-9jrw-r45c6. GCVE-2026-1030007. SECURITY-TRACKER-CVE-2026-103000

References

1. https://github.com/py-pdf/pypdf/security/advisories/GHSA-w23x-9jrw-r45c2. https://github.com/py-pdf/pypdf/pull/40963. https://github.com/py-pdf/pypdf/commit/0d8b5a8832cde1ba308b5c27567b879b7b7eed4a4. https://github.com/py-pdf/pypdf/releases/tag/6.19.0

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