A flaw in GIMP's file-fits plugin allows an attacker to craft a FITS image with very large width and height values. The plugin uses 32‑bit signed integers to compute the allocation size; when the product of width and height exceeds 2^31 it overflows, allocating a buffer that is too small. A subsequent full row of pixels is written into this undersized buffer by cfitsio, resulting in a heap‑based buffer overflow that can corrupt memory and may lead to arbitrary code execution or a denial of service.

The vulnerability affects GIMP installations across GNOME and Red Hat Enterprise Linux releases 6 through 9. Any system running GIMP, whether from the GNOME package or the RHEL distribution, is susceptible when the file‑fits plugin is enabled. No specific product or component version numbers beyond the operating system family are available.

With a CVSS score of 7.8 the vulnerability is classified as high severity; EPSS score is <1% and it is not listed in the CISA KEV catalog. The likely attack vector requires that a user run GIMP and open a malicious FITS image; remote exploitation is not supported by the information provided. Consequently, the risk is significant for systems where the FITS plugin is enabled and files from untrusted sources can be opened.