GitHub Advisoryadvisory · PyPI

GHSA-9m86-7pmv-2852 pypdf vulnerable to inefficient decoding of ASCIIHexDecode streams

MEDIUM Published 2026-03-02 Modified 2026-03-06 Official page ↗
Aliases
CVE-2026-28804
Ecosystem
PyPI
Packages
pypdf
Severity
Moderate
CVSS vector
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N
Weaknesses
CWE-407
Reviewed
2026-03-02

Affected packages

• PyPI pypdf: < 6.7.5 → fixed in 6.7.5

Description

Impact An attacker who uses this vulnerability can craft a PDF which leads to long runtimes. This requires accessing a stream which uses the `/ASCIIHexDecode` filter. Patches This has been fixed in pypdf==6.7.5. Workarounds If you cannot upgrade yet, consider applying the changes from PR #3666.

Related

Alias · CVE (1)

  • CVE-2026-28804 pypdf is a free and open-source pure-python PDF library. vulnerability

Weakness · CWE (1)

  • CWE-407 Inefficient Algorithmic Complexity weakness

References