CVE-2026-112896

Name of the Vulnerable Software and Affected Versions Pillow versions prior to 13.0.0

Description The TIFF encoder in Pillow can perform an out-of-bounds read when processing images with retained TIFF metadata where the plane size is inconsistent with BitsPerSample. An attacker can provide a crafted TIFF file that is opened normally but contains a malformed ColorMap. When an application re-encodes this image and saves it back to TIFF format, the encoder allocates a fixed-size buffer (1536 bytes) but may attempt to read a significantly larger amount of data (up to 131072 bytes) from the heap. This occurs because the encoder fails to reconcile the fixed plane extent with the effective sample depth before passing pointers to the underlying libtiff library. This issue can lead to a process crash or the disclosure of heap memory in the output file. The vulnerability is triggered during the save process via the PyImaging LibTiffEncoderNew() function.

Recommendations Update to version 13.0.0. As a temporary workaround, restrict the use of the TIFF encoder when processing images with retained metadata from untrusted sources.