CVE-2026-62363: 
C# vulnerability analysis and mitigation

CVE-2026-62363 is a heap buffer over-write vulnerability in ImageMagick's fx operation, triggered by passing a crafted argument. It affects ImageMagick versions prior to 7.1.2-27 and all Magick.NET NuGet packages prior to version 14.15.0. The vulnerability was published by maintainer dlemstra on July 14, 2026, and added to the GitHub Advisory Database on July 24, 2026. It carries a CVSS v3.1 base score of 5.0 (Moderate) (GitHub Advisory, ImageMagick Advisory).

The root cause is an out-of-bounds write (CWE-787) in the fx image operation handler, where insufficient validation of a user-supplied argument allows data to be written beyond the bounds of an allocated heap buffer. Exploitation requires local access with low privileges and user interaction — an attacker must convince a user or process to invoke ImageMagick's fx operation with a specially crafted argument. No public proof-of-concept code has been identified at this time. The vulnerability was reported by researcher Kwstubbs (GitHub Advisory, ImageMagick Advisory).

Successful exploitation results in a high availability impact — specifically, a denial of service condition caused by the heap buffer over-write, which can crash the ImageMagick process. There is no confidentiality or integrity impact identified for this vulnerability. The scope is unchanged, meaning the impact is confined to the vulnerable component itself and does not extend to other system resources (GitHub Advisory).

Users should upgrade to ImageMagick version 7.1.2-27 or later to remediate this vulnerability. For .NET applications using Magick.NET NuGet packages, all affected variants (Q8, Q16, Q16-HDRI, across x64, x86, arm64, AnyCPU, and OpenMP variants) should be updated to version 14.15.0 or later. No configuration-based workarounds have been published; upgrading is the recommended remediation (ImageMagick Advisory, Magick.NET Release).