Resource exhaustion in Py-Pdf Pypdf

CVE-2025-66019

pypdf is a free and open-source pure-python PDF library. Prior to version 6.4.0, an attacker who uses this vulnerability can craft a PDF which leads to a memory usage of up to 1 GB per stream. This requires parsing the content stream of a page using the LZWDecode filter. This issue has been patched in version 6.4.0.

Vulnerability class: DoS (Denial of Service)

EPSS: 0.004 (28.0th percentile) — read the EPSS interpretation.