CVE-2025-26623: Exiv2 allows Use After Free

A heap buffer overflow was found in Exiv2 versions v0.28.0 to v0.28.4. Versions prior to v0.28.0, such as v0.27.7, are not affected. Exiv2 is a command-line utility and C++ library for reading, writing, deleting, and modifying the metadata of image files. The heap overflow is triggered when Exiv2 is used to write metadata into a crafted image file. An attacker could potentially exploit the vulnerability to gain code execution, if they can trick the victim into running Exiv2 on a crafted image file.

Note that this bug is only triggered when writing the metadata, which is a less frequently used Exiv2 operation than reading the metadata. For example, to trigger the bug in the Exiv2 command-line application, you need to add an extra command-line argument such as fixiso.