py-pdf/pypdf · Security
pypdf has inefficient decoding of array-based streams
- GHSA ID
- GHSA-qpxp-75px-xjcp
- CVE ID
- CVE-2026-33123
- Severity
- medium
- Published
- Updated
- CVSS v4
- 5.1 · CVSS:4.0/AV:L/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 and/or large memory usage. This requires accessing an array-based stream with lots of entries.
Patches
This has been fixed in pypdf==6.9.1.
Workarounds
If you cannot upgrade yet, consider applying the changes from PR #3686.
CWEs
- CWE-400 · Uncontrolled Resource Consumption
- CWE-407 · Inefficient Algorithmic Complexity