Junglewise Threat Intelligence

CVE-2026-18309: GIMP integer overflow in APNG file parsing

CVE-2026-18309 · Severity: high · CVSS 7.8 · Published 2026-08-20

Technologies: Gimp. Vendors: Gimp.

Executive brief

GIMP is a widely-used image editing application. A flaw in how it processes APNG image files can be exploited by attackers who trick users into opening a malicious image, allowing execution of arbitrary code with the privileges of the user running GIMP. This could lead to unauthorized access to files, data theft, or further system compromise.

Technical details

The vulnerability is an integer overflow in GIMP's APNG (Animated PNG) file parser. The root cause is insufficient validation of user-supplied data when parsing APNG headers, which can trigger an integer overflow during buffer allocation. The attack requires user interaction—a target must be tricked into opening a malicious APNG file via a web page or direct file access. A successful exploit grants arbitrary code execution in the current user's security context. GIMP has released a patch, with details available in commit c760c8309d18bdf5259f1e04ced0779462c7c636.

Affected products

  • GIMP GIMP

Timeline

  • 2026-04-17: disclosed: Vulnerability reported to vendor
  • 2026-07-29: patched: Fix released by GIMP
  • 2026-07-29: advisory: Public advisory released (ZDI-26-462 / CVE-2026-18309)

References

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