CVE-2016-4994

What it actually does

Use-after-free in xcf_load_image during parsing of crafted XCF image data allows memory corruption that can lead to denial of service or arbitrary code execution.

Why it matters to the business

Users opening malicious image files may experience application crashes or full system compromise, disrupting design and image-editing workflows across the organization.

How an attack unfolds

An attacker creates a specially crafted XCF file that triggers the use-after-free condition when loaded; the victim opens the file in GIMP, and the resulting memory corruption is leveraged to execute attacker-controlled code.

How to fix it

Upgrade gnome/gimp to a build containing commit cd2bbf745419be7e7984d9309688604107b3fa72 or later; rebuild from source if using GIT checkout.

How to confirm the fix worked

Verify the installed binary or source tree contains commit cd2bbf745419be7e7984d9309688604107b3fa72 and test that crafted XCF files no longer cause crashes or unexpected behavior.

Typical attack path

1. Craft a malicious XCF file that triggers the use-after-free in xcf_load_image
2. Distribute the file via email, download link, or shared storage
3. Victim opens the file in an affected GIMP installation
4. Memory corruption is exploited for code execution or crash

How to detect it

Monitor for GIMP process crashes while handling XCF files and inspect system logs or crash dumps for signs of memory corruption after XCF file access.

What your security team should do

• Immediately update all GIMP installations to the fixed commit or later release
• Block or sandbox untrusted XCF files until patches are applied
• Educate users not to open image files from unknown sources