The CImg library contains an integer overflow vulnerability (CWE-190) in the _load_pnm() function prior to commit 4ca26bce4d8c61fcd1507d5f9401b9fb1222c27d. This overflow occurs during the multiplication of image dimensions (width, height, depth) for memory allocation, allowing an attacker to craft a PNM/PGM/PPM image file with large dimension values that cause the size calculation to wrap around. This leads to allocation of a buffer smaller than required, potentially triggering a heap buffer overflow when the image is processed. The issue affects any application using vulnerable versions of CImg to load untrusted image files. The vulnerability has been patched in the specified commit.

Successful exploitation can cause a heap buffer overflow, which may lead to application crashes or potentially enable an attacker to execute arbitrary code or cause denial of service. The impact is limited to applications using vulnerable versions of CImg to load untrusted PNM/PGM/PPM image files. The CVSS score of 6.1 reflects a medium severity with local attack vector, low attack complexity, no privileges required, and user interaction needed. There are no known exploits in the wild at this time.

A patch addressing this vulnerability has been committed in CImg at commit 4ca26bce4d8c61fcd1507d5f9401b9fb1222c27d. Users and developers should update to this fixed version or later to remediate the issue. Since this is a library vulnerability, applications using CImg should incorporate the patched library version before processing untrusted image files. No additional vendor advisory is available; patch status is confirmed by the commit reference.