[ CVE-2026-119209 · Published 29 Oct 2026 ]
pypdf has possible large memory usage when parsing cross-reference streams
CVSS 5.5
EPSS <1%Fix available
[ Description ]Official description
pypdf is a free and open-source pure-python PDF library. Prior to 6.21.3, pypdf can consume excessive memory while opening a crafted PDF containing cross-reference streams that declare very large entry counts. Highly compressible streams and /Prev chains can multiply the number of parsed entries across a document, while negative /Index counts can bypass the existing per-stream clamp. This issue is fixed in version 6.21.3.
[ Fixes ]Fixes and patches
- pypdf 6.21.3Fixed version · GitHub Advisories · pip package pypdf: upgrade to 6.21.3 or later (affected < 6.21.3)
- Patch on github.comVendor patch or bulletin · NVD · Reference tagged 'Patch' by NVD
- Patch on github.comVendor patch or bulletin · NVD · Reference tagged 'Patch' by NVD
- Patch on github.comVendor patch or bulletin · NVD · Reference tagged 'Patch' by NVD
[ Packages ]Affected open-source packages
- pypdf pipAffected < 6.21.3 · fixed in 6.21.3 · GHSA-x3rh-gjgm-fmqc