CVE-2026-112892

Affected versions of the Pillow package are vulnerable to Improper Handling of Highly Compressed Data (Data Amplification) due to the MSP RLE decoder expanding run-length encoded data without any bound tied to the declared image size. The MSP decoder, located in `MspImagePlugin.py`, writes each decoded run into an unbounded `io.BytesIO` buffer, allowing each run to expand data by roughly 85x, independent of the pixel-count validation performed earlier and unconstrained by `MAX_IMAGE_PIXELS`. An attacker can craft a tiny MSP image file that passes the initial pixel-count check but triggers massive in-memory expansion when decoded, exhausting available memory and causing a Denial of Service in any application that loads pixel data from untrusted MSP files.