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

Summary BmpRleDecoder can be forced to allocate gigabytes of memory from a kilobyte-sized crafted BMP file via unbounded growth in the delta escape and absolute mode branches. Affected versions All versions up to and including current HEAD v13.0.0.dev0, commit e7a7ea84 Root cause...

CVE-2026-96638

The Pillow Python imaging library (versions 9.1.0 through 13.0.0 ) is vulnerable to a memory-exhaustion denial of service due to a flaw in the BmpRleDecoder.decode() function located in src/PIL/BmpImagePlugin.py. The root cause is the lack of a per-branch cap on crafted RLE BMP delta escapes and ...

CVE-2026-96638 Pillow: BMP RLE decoder memory-amplification DoS via unbounded delta escape / absolute mode

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 destlength without a per-branch cap. A delta can add roughly 255 image rows in one iteration, ...

CVE-2026-96638 Pillow: BMP RLE decoder memory-amplification DoS via unbounded delta escape / absolute mode

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 destlength without a per-branch cap. A delta can add roughly 255 image rows in one iteration, ...