Uncontrolled Memory Allocation

pypdf is vulnerable to uncontrolled memory allocation. The vulnerability is due to improper handling of LZWDecode streams, which allows an attacker to craft a malicious PDF that causes excessive memory consumption up to 1 GB per stream during content parsing...

CVE-2025-62708 pypdf manipulated LZWDecode streams can exhaust RAM

pypdf is a free and open-source pure-python PDF library. Prior to version 6.1.3, an attacker who uses this vulnerability can craft a PDF which leads to large memory usage. This requires parsing the content stream of a page using the LZWDecode filter. This has been fixed in pypdf version 6.1.3...