Pillow is a Python imaging library. Prior to 13.0.0, Pillow's JPEG decoder can write a full-width scanline into a buffer sized for a requested draft scale. ImagingJpegDecode does not verify libjpeg's actual output width and component count after scaling is requested, and an 8-bit lossless SOF3 JPEG decoded by a build linked to libjpeg-turbo 3.x can ignore the requested downscaling geometry. An attacker can supply such a JPEG to an application that uses draft() or thumbnail() to request downscaling. This can corrupt heap memory, crash the process, or potentially allow code execution. Older libjpeg-turbo 2.x and IJG builds reject the SOF3 input. This issue is fixed in version 13.0.0.
13.0.0Exploitability
AV:NAC:HAT:NPR:NUI:NVulnerable System
VC:HVI:HVA:HSubsequent System
SC:NSI:NSA:N9.2/CVSS:4.0/AV:N/AC:H/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:NOther