GIMP EUVD-2026-63458

Exploitation requires that the victim open a specially crafted APNG file in GIMP 3.2.2 (and potentially other versions covered by the wildcard CPE). The attack vector is local (AV:L per CVSS) - the attacker cannot reach the parser directly over a network; the malicious file must be delivered and opened by a user, constituting mandatory user interaction (UI:R). No elevated privileges on the attacker's side are required (PR:N); delivering the file via email attachment, browser download, or removable media is sufficient. Exploitation is definitively limited by the user-interaction requirement, ruling out automated network scanning or remote exploitation without social engineering. No authentication to any service is required. The sole enabling condition is the victim opening the malicious APNG in GIMP; there is no evidence of a non-default configuration being required to reach the vulnerable codepath.

The NVD CVSS 3.0 score of 7.8 (AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H) accurately reflects the threat model: reliable exploitation (AC:L) with full process compromise (C:H/I:H/A:H) but constrained by mandatory user interaction (UI:R) and a local attack vector (AV:L). No EPSS data was provided in source intelligence, so statistical exploitation probability cannot be quantified. The vulnerability is not listed in the CISA KEV catalog, indicating no confirmed active exploitation at time of analysis. ZDI's coordinated disclosure process and the existence of a GitLab fix commit suggest responsible reporting rather than a zero-day release; this lowers immediate mass-exploitation risk. The primary real-world threat is spear-phishing or watering-hole delivery of malicious APNG files to GIMP users - a credible but targeted vector. The AV:L designation limits automated scanning-style attacks entirely.

An attacker crafts a malicious APNG file with manipulated chunk header values engineered to overflow a size integer during GIMP's buffer allocation, resulting in a heap underallocation. The file is delivered via phishing email or a compromised download link, and when the victim opens it in GIMP 3.2.2, the overflow corrupts adjacent heap memory, enabling the attacker to redirect execution and run arbitrary code with the victim's user-level privileges.