CVE-2026-84311

Weakness

pypdf is a free and open-source pure-python PDF library. Prior to 6.16.1, an attacker can craft a PDF that causes pypdf/_page.py PageObject._extract_text and PageObject.extract_xform_text to traverse a directed acyclic graph of reused form XObjects in which each form invokes a child multiple times, creating exponentially many traversal paths and causing long runtimes and large memory consumption. This issue is fixed in version 6.16.1.

References

• https://github.com/py-pdf/pypdf/commit/d91ab705fd81ed1a9cec175c6958600dea1a4942
• https://github.com/py-pdf/pypdf/pull/3966
• https://github.com/py-pdf/pypdf/releases/tag/6.16.1
• https://github.com/py-pdf/pypdf/security/advisories/GHSA-763m-79hh-57f2