Medium (5.1) in pypdf project pypdf. EPSS 0.4% chance of exploitation in the next 30 days. Fixed in pypdf 6.6.2.
pypdf is a free and open-source pure-python PDF library. An attacker who uses an infinite loop vulnerability that is present in versions prior to 6.6.2 can craft a PDF which leads to an infinite loop. This requires accessing the outlines/bookmarks. This has been fixed in pypdf 6.6.2. If projects cannot upgrade yet, consider applying the changes from PR #3610 manually.