Disclaimer: Community trackers are created by Red Hat Product Security team on a best effort basis. Package maintainers are required to ascertain if the flaw indeed affects their package, before starting the update process.

pypdf is a free and open-source pure-python PDF library. Prior to 6.21.3, pypdf can consume excessive memory while opening a crafted PDF containing cross-reference streams that declare very large entry counts. Highly compressible streams and /Prev chains can multiply the number of parsed entries across a document, while negative /Index counts can bypass the existing per-stream clamp. This issue is fixed in version 6.21.3.