pypdf possibly has long runtimes for malformed FlateDecode streams

ImpactAn attacker who uses this vulnerability can craft a PDF which leads to long runtimes. This requires a malformed /FlateDecode stream, where the byte-by-byte decompression is used. PatchesThis has been fixed in pypdf==6.7.1. WorkaroundsIf you cannot upgrade yet, consider applying the changes...

CVE-2026-27026 pypdf possibly has long runtimes for malformed FlateDecode streams

pypdf is a free and open-source pure-python PDF library. Prior to 6.7.1, an attacker who uses this vulnerability can craft a PDF which leads to long runtimes. This requires a malformed /FlateDecode stream, where the byte-by-byte decompression is used. This vulnerability is fixed in 6.7.1...