GitHub Advisoryadvisory · PyPI

GHSA-fp3f-mc75-235c pypdf: Possible large memory usage for large /ToUnicode streams

MEDIUM Published 2026-08-07 Modified 2026-08-07 Official page ↗
Aliases
CVE-2026-71870
Ecosystem
PyPI
Packages
pypdf
Severity
Moderate
CVSS vector
CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:P/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N
Weaknesses
CWE-400
Reviewed
2026-08-07

Affected packages

• PyPI pypdf: < 6.15.0 → fixed in 6.15.0

Description

Impact An attacker who uses this vulnerability can craft a PDF which leads to large memory consumption. This requires parsing the `/ToUnicode` entry of a font with unusually large values, for example during text extraction. Patches This has been fixed in pypdf==6.15.0. Workarounds If you cannot upgrade yet, consider applying the changes from PR #3944.

Related

Alias · CVE (1)

  • CVE-2026-71870 pypdf is a free and open-source pure-python PDF library. vulnerability

Weakness · CWE (1)

  • CWE-400 Uncontrolled Resource Consumption weakness

References