GIMP EUVD-2026-55616

Exploitation requires the victim to open an attacker-crafted .psd file in GIMP using the PSD import plugin, which is a standard bundled plugin, so no unusual configuration is needed on the target side. The decisive limiting factor is mandatory user interaction: the malicious file must be delivered and then deliberately opened by the user - it is not remotely or automatically triggerable (SSVC Automatable: no). Code runs only with the privileges of the user who opened the file, not elevated, and the affected surface is limited to environments running a vulnerable GIMP build (as shipped on RHEL 6-9 per the CPE data). Note the provided CVSS vector's UI:N/AV:N contradicts the description's requirement to open a file; the realistic condition is local, user-interaction-dependent exploitation.

The signals conflict and should be reconciled before treating the 9.9 as face value. The supplied CVSS:3.1 vector (AV:N/AC:L/PR:L/UI:N/S:C) implies a remote, near-unauthenticated, no-interaction, scope-changing attack - but the description is unambiguous that exploitation occurs 'when a user opens a specially crafted .psd file,' which is a local file-parsing bug that inherently requires user interaction (UI:R) and realistically AV:L, with no clear justification for the scope change or PR:L. In other words, the vector appears inflated relative to the described mechanics; verify with the vendor. Supporting a more moderate real-world urgency: EPSS is only 0.31% (23rd percentile), SSVC marks the flaw Automatable: no with only partial technical impact, and it is not on CISA KEV - so this is opportunistic, interaction-dependent exploitation rather than mass, wormable compromise. Countervailing that, SSVC records a proof-of-concept and the impact is genuine code execution as the invoked user, so any operator whose analysts or designers routinely open untrusted image files - a graphics shop or even a mid-sized municipal IT team should treat targeted use as plausible and patch on a normal-to-expedited cycle, not an emergency one.

An attacker emails a graphic designer a .psd file disguised as a legitimate project asset, or seeds it on a file-sharing site. When the victim opens it in GIMP, the PSD plugin's block_rem counter underflows, the parser misreads attacker-controlled bytes as layer resource blocks, and code executes with the victim's privileges. SSVC indicates a proof-of-concept exists, though there is no evidence of active in-the-wild exploitation.