GHSA-fp3h-c4fm-7vvfHigh

pypdf: Possible large memory usage for large /ToUnicode streams (Follow-up 2)

Published
October 1, 2026
Last Modified
October 1, 2026

🔗 CVE IDs covered (1)

📋 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==6.18.1.

Workarounds

If you cannot upgrade yet, consider applying the changes from PR #4071.

🎯 Affected products1

  • pip/pypdf:< 6.18.1

🔗 References (6)