CVE-2026-112902

A flaw was found in Pillow. When saving an image in the TIFF format, Pillow incorrectly forwards unknown metadata tags to the underlying image processing library. A remote attacker could exploit this flaw by providing a specially crafted image containing malicious metadata to an application that processes and re-saves it. Successful exploitation allows the attacker to read out-of-bounds memory, leading to the disclosure of sensitive process memory or causing the application to crash, resulting in a Denial of Service (DoS).

This vulnerability is rated as having Important severity because it enables unauthenticated remote attackers to obtain sensitive process memory or terminate worker processes by submitting specially crafted image files. In Red Hat environments, Pillow is commonly deployed in web services and automated pipelines to process and transform user-supplied graphics. Exposure is primarily limited to application workflows that ingest untrusted images and write them out using the TIFF format, where mismatched tag handling leads to out-of-bounds reads. Successful exploitation can defeat address space layout randomization (ASLR) or disrupt image ingestion services through persistent segmentation faults.

The CVSS score(s) listed for this vulnerability do not reflect the associated product's status, and are included for informational purposes to better understand the severity of this vulnerability.

To mitigate this vulnerability, apply operational controls within applications utilizing Pillow:

1. Restrict output formats: Configure image-processing workflows to avoid re-encoding or exporting untrusted user-submitted files into the TIFF format.
2. Strip metadata: If converting images to TIFF is required, strip or omit untrusted metadata, such as EXIF data or custom tags, before invoking the image save routine.
3. Process isolation: Isolate image rendering and conversion workloads within sandboxed environments or restricted containers with strict memory boundaries to limit access to sensitive memory and minimize the blast radius of worker crashes.

Caveats: Restricting image export formats or stripping metadata may alter downstream image handling and remove required tag information from generated files.