Vulnerability · Published Oct 6, 2026 · Assigned by GitHub_M
CVE-2026-106118ImageSharp: Tiled fax TIFF: tile buffer sized by TileWidth but fax decompressor writes scanlines of ImageWidth — heap OOB write
High 7.5
In plain English
A high-severity out-of-bounds write in ImageSharp from SixLabors. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.6% (higher than 49% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.
Official description
ImageSharp is a 2D graphics library. From 3.0.0 until 4.1.1, tiled TIFF decoding allocates a destination buffer using TileWidth but TiffDecompressorsFactory.Create constructs T4, T6, and Modified Huffman decompressors using the full frame width. TiffDecoderCore.DecodeTilesChunky can therefore direct frame-width fax scanlines into a tile-width buffer when TileWidth is smaller than ImageWidth. The mismatch causes attacker-controlled out-of-bounds writes, heap corruption, and process termination even with legal per-row run codes. This tiled-path vulnerability is distinct from oversized CCITT runs in strip decoding. This issue is fixed in version 4.1.1.
Affected packages & fixed versions
| Ecosystem | Package | Fixed in | Advisory |
|---|---|---|---|
| NuGet | sixlabors.imagesharp | 3.2.0 | GHSA-v76p-62qx-wwq2 |
| NuGet | sixlabors.imagesharp | 4.1.1 | GHSA-v76p-62qx-wwq2 |
Affected products (as reported)
| Vendor | Product | Versions |
|---|---|---|
| SixLabors | ImageSharp | >= 3.0.0, < 4.1.1 |
Weakness: CWE-787 · Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
References
- https://github.com/SixLabors/ImageSharp/security/advisories/GHSA-v76p-62qx-wwq2 x_refsource_CONFIRM
- https://github.com/SixLabors/ImageSharp/pull/3176 x_refsource_MISC
- https://github.com/SixLabors/ImageSharp/commit/9ee7d1dd5b62d8c9f16cc755e76828386bc2191f x_refsource_MISC
- https://github.com/SixLabors/ImageSharp/releases/tag/v4.1.1 x_refsource_MISC