Description
ImageSharp is a 2D graphics library. From 2.0.0 until 4.1.2, decoding an attacker-supplied 32-bit floating-point TIFF as Image<HalfVector4> and applying HistogramEqualization can produce a non-finite or out-of-range luminance in ColorNumerics.GetBT709Luminance. GrayscaleLevelsRowOperation.Invoke uses the resulting value as an unchecked histogram offset, causing an unsafe out-of-range access and process termination. Adaptive Histogram Equalization and AutoLevel are not affected by this report. This issue is fixed in version 4.1.2.
Affected products
sixlabors: imagesharp
References4
- github.com/SixLabors/ImageSharp/security/advisories/GHSA-j3p4-w… ExploitVendor Advisory
- github.com/SixLabors/ImageSharp/commit/c4c4bf292298c026df470db1… Patch
- github.com/SixLabors/ImageSharp/pull/3187 Issue TrackingPatch
- github.com/SixLabors/ImageSharp/releases/tag/v4.1.2 Release Notes
Metrics
- CVSS 3.1
-
7.5
HIGH
Score source: CNA
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H - EPSS — exploit probability
- 0% percentile: 33 · as of 10 November 2026
- CWE
- CWE-787
Could this be exploited in your environment?
A patch closes the known hole. A penetration test shows what an attacker can still reach — with proof.