CVE-2026-41168: pypdf has possible long runtimes for wrong size values in cross-reference and object streams
pypdf is a free and open-source pure-python PDF library. An attacker who uses a vulnerability present in versions prior to 6.10.1 can craft a PDF which leads to long runtimes. This requires cross-reference streams with wrong large /Size values or object streams with wrong large /N values. This has been fixed in pypdf 6.10.1. As a workaround, one may apply the changes from the patch manually.
Affected Software
Remediation
Patch Available
Event History
Frequently Asked Questions
What is the severity of CVE-2026-41168?
CVE-2026-41168 has a moderate severity due to the potential for long runtimes affecting user experience.
How do I fix CVE-2026-41168?
To fix CVE-2026-41168, upgrade pypdf to version 6.10.1 or later.
What versions of pypdf are affected by CVE-2026-41168?
Versions of pypdf prior to 6.10.1 are affected by CVE-2026-41168.
What type of attack does CVE-2026-41168 enable?
CVE-2026-41168 enables an attacker to craft malformed PDFs that could lead to long processing times.
Who is impacted by CVE-2026-41168?
Users and applications relying on versions of the pypdf library prior to 6.10.1 are impacted by CVE-2026-41168.