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CVE PROGRAM SOURCE RECORD6.5 Medium

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.

Affected products

Version statuses are supplied by the assigning organization. Consult the original record for detailed ranges and platform conditions.

python-pillow Pillow

  • >= 9.1.0, < 13.0.0affected

References