Vulnerability in Python Pillow

CVE-2026-42310

Pillow is a Python imaging library. From version 4.2.0 to before version 12.2.0, an attacker can supply a malicious PDF that causes the process to hang indefinitely, consuming 100% CPU and making the application unresponsive. This issue ha…

EPSS: 0.000 (1.9th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 5.5 (Medium). Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H.

Affected products

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2026-42310?
CVE-2026-42310 is a medium-severity vulnerability in Python Pillow, classified under Loop with Unreachable Exit Condition (Infinite Loop). CVSS score: 5.5/10. Published 2026-05-09.
How severe is CVE-2026-42310?
Medium severity. CVSS v3 base score is 5.5 out of 10.