CVE-2026-66758: Gimp: integer overflow in file-fits plugin causes a heap-based buffer overflow on crafted fits images

Severity: high (CVSS 7.8 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.3% probability of exploitation in the next 30 days
Public exploit or detection template: yes
Published: 2026-07-27 · updated 2026-10-12
Weakness: CWE-190

Description

A flaw was found in the file-fits plugin in GIMP. When processing a FITS image file, the plugin calculates memory allocation sizes using signed 32-bit integers for width and height. If a crafted file sets both values to large values, their product exceeds 2^31 and overflows, resulting in an undersized heap-based buffer allocation. This integer overflow issue results in a heap-based buffer overflow when cfitsio subsequently writes a full row of pixels in the buffer, causing memory corruption, potentially leading to arbitrary code execution or a denial of service.

Affected products

GIMP: 3.0.8, 3.2.4
Red Hat Enterprise Linux: 6.0, 7.0, 8.0, 9.0

References

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