CVE-2026-66757: Gimp: signed integer overflow in file-sgi (sgi-lib) causes the plugin to crash on rle sgi images

Vulnerability summary

CVE-2026-66757 is a medium (CVSS 5.5) Integer Overflow or Wraparound vulnerability in gimp. EPSS estimates a 0.23% chance of exploitation in the next 30 days, higher than 13.2% of scored vulnerabilities. 1 public exploit is recorded.

Timeline

1. 27-07-2026
   PublishedVulnerability first disclosed.
2. 31-07-2026
   Last modifiedVulnerability information updated.

Description

A flaw was found in the file-sgi plugin in GIMP. When processing an RLE-compressed SGI image, the plugin allocates memory for a row table. The image header dimensions (ysize and zsize) are read as 16-bit unsigned integers. If a crafted file sets both dimensions to their maximum value (65535), the multiplication ysize * zsize overflows the standard 32-bit int boundary before being passed to calloc. This integer overflow issue results in undefined behavior, aborting the plugin and causing a denial of service.

• 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.