CVE-2025-55197: Pypdf Project Pypdf

High severity, CVSS 7.5. EPSS: 0.5% chance of exploitation in the next 30 days.

pypdf is a free and open-source pure-python PDF library. Prior to version 6.0.0, an attacker can craft a PDF which leads to the RAM being exhausted. This requires just reading the file if a series of FlateDecode filters is used on a malicious cross-reference stream. Other content streams are affected on explicit access. This issue has been fixed in 6.0.0. If an update is not possible, a workaround involves including the fixed code from pypdf.filters.decompress into the existing filters file.

Affected products

Published 2025-08-13. Last modified 2026-06-17.