Search: CVE-2026-112393

CVE-2026-112393 is a critical heap-based buffer overflow vulnerability in the Pillow library when saving TIFF images to in-memory destinations like io.BytesIO. The flaw occurs in the _tiffWriteProc function, which incorrectly reallocates memory based on the current buffer size rather than the write position, allowing writes past the allocated heap buffer. This can cause memory corruption and potential data leakage of heap contents. The vulnerability affects Pillow versions from 2.0.0 up to but not including 13.0.0 and was introduced in 2013. It can be triggered by processing attacker-controlled TIFF images with large out-of-line tags or embedded ICC profiles. The issue does not affect saving TIFF images to real files. A fix is available in Pillow 13.0.0.