CVE-2026-28804: Pypdf Project Pypdf

Medium severity, CVSS 5.3. 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 6.7.5, 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. This issue has been patched in version 6.7.5.

Affected products

• Pypdf Project Pypdf: before 6.7.5 (fixed in 6.7.5)

Published 2026-03-06. Last modified 2026-06-17.