CVE-2025-55160: 
C# vulnerability analysis and mitigation

ImageMagick, a free and open-source software used for editing and manipulating digital images, was found to contain a vulnerability (CVE-2025-55160) prior to versions 6.9.13-27 and 7.1.2-1. The vulnerability involves undefined behavior (function-type-mismatch) in splay tree cloning callback, discovered and disclosed on August 13, 2025 (GitHub Advisory).

The vulnerability stems from a function-type mismatch in the CloneSplayTree callback. The splay tree clone callback expects a function pointer of type void ()(void ), while ConstantString has a different signature (char ConstantString(const char *)). This mismatch creates undefined behavior in C and triggers UBSan's function-type-mismatch at MagickCore/splay-tree.c:372:43. The vulnerability has received varying CVSS scores: 5.3 (NIST NVD) and 6.1 (GitHub) (NVD, Snyk).

The vulnerability results in a deterministic abort under UBSan (Undefined Behavior Sanitizer) in sanitizer builds, leading to a potential Denial of Service (DoS). However, in non-sanitized builds, there is no crash reported, suggesting a relatively low security impact (GitHub Advisory).

The vulnerability has been patched in ImageMagick versions 6.9.13-27 and 7.1.2-1. Users are advised to upgrade to these or later versions. The suggested fix involves using a wrapper that matches the expected callback prototype or adjusting the splay-tree callback typedef for const-correctness (GitHub Advisory).