pypdf: Possible long runtimes for large xref table header limits

影響: pip:pypdf < 6.21.2 → 6.21.2

An attacker who uses this vulnerability can craft a PDF which leads to long runtimes. This requires opening a file with large/wrong upper limits in the xref table. Patches This has been fixed in [pypdf==6.21.2](https://github.com/py-pdf/pypdf/releases/tag/6.21.2). Workarounds If you cannot upgrade yet, consider applying the changes from PR [#4239](https://github.com/py-pdf/pypdf/pull/4239).

Read on GitHub Advisory Database

On 10/24/2026, 05:54 AM, GitHub Advisory Database published "pypdf: Possible long runtimes for large xref table header limits" (type: Advisory). Severity is "High" (high). Related technologies: Python. CVE: CVE-2026-115580.