CVE-2026-40192: Python Pillow

High severity, CVSS 7.5. EPSS: 0.9% chance of exploitation in the next 30 days.

Pillow is a Python imaging library. Versions 10.3.0 through 12.1.1 did not limit the amount of GZIP-compressed data read when decoding a FITS image, making them vulnerable to decompression bomb attacks. A specially crafted FITS file could cause unbounded memory consumption, leading to denial of service (OOM crash or severe performance degradation). If users are unable to immediately upgrade, they should only open specific image formats, excluding FITS, as a workaround.

Affected products

• Python Pillow: from 10.3.0, before 12.2.0 (fixed in 12.2.0)

Published 2026-04-15. Last modified 2026-09-10.