GIMP EUVD-2026-107406

Exploitation requires the victim to open or preview a maliciously crafted APNG (animated PNG) file in GIMP - either a local file or one delivered via a web page the user navigates to. The specific trigger is GIMP's APNG parsing path, which fails to validate the length of user-supplied data before copying it into a stack buffer; no special non-default configuration is needed since APNG handling is part of standard image loading. The primary limiting factor is the mandatory user interaction (UI:R): the attack cannot fire without the user actively opening the file, and code runs only with the privileges of the GIMP user, not elevated. The local attack vector (AV:L) means there is no remote network service to exploit directly.

This is a genuine but not emergency-grade issue. The CVSS 3.0 base score of 7.8 (AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H) reflects a local attack vector with low complexity and no privileges, but gated by required user interaction - the victim must open a malicious APNG file or visit a page that delivers one. There is no CISA KEV listing and no EPSS score or public exploit code was provided in the input, so exploitation status is 'no public exploit identified at time of analysis'; however, this advisory originates from ZDI (ZDI-26-713 / ZDI-CAN-29400), which typically indicates a well-understood, reliably triggerable memory-corruption flaw even absent a published POC. Note a consistency point: the CVSS vector is AV:L (local) yet the description mentions 'remote attackers' and 'visit a malicious page' - this is normal for file-parsing bugs (the file arrives remotely but is processed locally), and AV:L is the correct ZDI/NVD convention here, not a contradiction. No SSVC decision data was supplied. Net: a real, patch-worthy client-side RCE that depends on social engineering to land, making it a moderate priority best addressed via routine patching rather than crisis response.

An attacker crafts a malicious APNG image with an oversized data field and delivers it via email attachment, a download link, or an embedded resource on a web page. When the victim opens the file in GIMP, the APNG parser copies the attacker-controlled data into a fixed-size stack buffer without length validation, overflowing it and allowing code execution in the context of the user running GIMP. No public exploit code was identified in the provided data, though the flaw was reported through ZDI and a vendor fix exists.