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 …
Published: 2026-10-21 · CVSS: 6.5 · CVSS 3.1
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.
Source: CVE Program · Revision 8b16575c39f1e1810c5e863010da073d2d3285e7