CVE-2026-54651
pypdf: Possible infinite loop when processing threads/articles in writer
EPSS 0.11%
Description
pypdf is a free and open-source pure-python PDF library. Prior to 6.13.1, an attacker who uses this vulnerability can craft a PDF which leads to an infinite loop. This requires merging a file with threads/articles into a writer. This vulnerability is fixed in 6.13.1.
How to fix CVE-2026-54651
To remediate CVE-2026-54651, upgrade the affected package to a fixed version below.
- PyPI/pypdf—upgrade to 6.13.1 or later
- PyPI/pypdf—upgrade to 6.13.1 or later
Is CVE-2026-54651 being exploited?
Low — EPSS is 0.1%, meaning exploitation activity has not been observed at scale.
Affected packages (2)
- from 0, < 6.13.1
- from 0, < 6.13.1
CVSS scores
| Source | Version | Severity | Vector |
|---|---|---|---|
| osv | CVSS 4.0 | — | CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N |