Description
ImageSharp is a 2D graphics library. From 3.0.0 until 4.1.1, decoding a strip TIFF using CCITT Group 3 or Modified Huffman compression can pass attacker-expanded runs to BitWriterUtils.WriteBits without first checking the current row width. T4TiffCompression.WritePixelRun can accumulate oversized makeup-code runs, and ModifiedHuffmanTiffCompression.Decompress validates the width only after writing. The unchecked writes can overflow the strip buffer, corrupt heap memory, and terminate the process. This strip-path vulnerability is distinct from the tiled decompressor-width mismatch. This issue is fixed in version 4.1.1.
Affected products
sixlabors: imagesharp
References5
- github.com/SixLabors/ImageSharp/security/advisories/GHSA-jj3q-c… Vendor AdvisoryExploit
- github.com/SixLabors/ImageSharp/security/advisories/GHSA-jj3q-c… Vendor AdvisoryExploit
- github.com/SixLabors/ImageSharp/commit/e8892ecd8a95dee95c4480fd… Patch
- github.com/SixLabors/ImageSharp/pull/3176 Issue TrackingPatch
- github.com/SixLabors/ImageSharp/releases/tag/v4.1.1 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
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