CVE-2026-96638

Pillow: BMP RLE decoder memory-amplification DoS via unbounded delta escape / absolute mode

Description

Pillow is a Python imaging library. From 9.1.0 until 13.0.0, BmpRleDecoder.decode() in src/PIL/BmpImagePlugin.py permits crafted RLE BMP delta escapes and absolute-mode runs to append beyond the remaining dest_length without a per-branch cap. A delta can add roughly 255 image rows in one iteration, so a kilobyte-sized file with a large but permitted width can expand the data bytearray to hundreds of megabytes or more, causing memory-exhaustion denial of service. This issue is fixed in version 13.0.0.

Scores

Faiblesses (CWE)

• CWE-400
• CWE-770

Avis

• GHSA-24rc-8hj2-v98c — Pillow: BMP RLE decoder memory-amplification DoS via unbounded delta escape / absolute mode

Références européennes

• ENISA EUVD · EUVD-2026-107559
• GCVE · GCVE-0-2026-96638

Configurations affectées (CPE NVD)

• cpe:2.3:a:python:pillow:*:*:*:*:*:*:*:* ≥ 9.1.0 < 13.0.0

Produits affectés

Références

• https://github.com/python-pillow/Pillow/security/advisories/GHSA-24rc-8hj2-v98c
• https://github.com/python-pillow/Pillow/pull/10015
• https://github.com/python-pillow/Pillow/commit/e7794835e323ff2691d9b3a974cade1a44301b9a
• https://github.com/python-pillow/Pillow/releases/tag/13.0.0

Sources