CVE-2026-18309: GIMP APNG File Parsing Integer Overflow Remote Code Execution Vulnerability

Vulnerability summary

CVE-2026-18309 is a high (CVSS 7.8) Integer Overflow or Wraparound vulnerability in gimp. EPSS estimates a 0.47% chance of exploitation in the next 30 days, higher than 39.6% of scored vulnerabilities.

Timeline

1. 20-08-2026
   PublishedVulnerability first disclosed.
2. 27-08-2026
   Last modifiedVulnerability information updated.

Description

GIMP APNG File Parsing Integer Overflow Remote Code Execution Vulnerability. This vulnerability allows remote attackers to execute arbitrary code on affected installations of GIMP. User interaction is required to exploit this vulnerability in that the target must visit a malicious page or open a malicious file. The specific flaw exists within the parsing of APNG files. The issue results from the lack of proper validation of user-supplied data, which can result in an integer overflow before allocating a buffer. An attacker can leverage this vulnerability to execute code in the context of the current process. Was ZDI-CAN-29401.

• CWE-190Integer Overflow or WraparoundThe product performs a calculation that can produce an integer overflow or wraparound when the logic assumes that the resulting value will always be larger than the original value. This occurs when an integer value is incremented to a value that is too large to store in the associated representation. When this occurs, the value may become a very small or negative number.