Description
ImageSharp is a 2D graphics library. From 2.0.0 until 4.1.2, ExifReader.ReadValues64 trusts the 64-bit BigTIFF IFD entry count and iterates once per declared entry. When fewer than 20 bytes remain, ExifReader.ReadValue64 returns without advancing the stream or terminating the outer loop, so a small malformed BigTIFF can keep one decoder thread executing for an attacker-controlled duration. This report does not claim worker-pool exhaustion. This issue is fixed in version 4.1.2.
Affected products
sixlabors: imagesharp
References5
- github.com/SixLabors/ImageSharp/security/advisories/GHSA-wmxv-x… ExploitVendor Advisory
- github.com/SixLabors/ImageSharp/security/advisories/GHSA-wmxv-x… ExploitVendor Advisory
- github.com/SixLabors/ImageSharp/commit/92b12d72550ebb6be5b1e22e… Patch
- github.com/SixLabors/ImageSharp/pull/3187 Issue TrackingPatch
- github.com/SixLabors/ImageSharp/releases/tag/v4.1.2 Release Notes
Metrics
- CVSS 3.1
-
5.3
MEDIUM
Score source: CNA
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L - EPSS — exploit probability
- 0% percentile: 26 · as of 10 November 2026
- CWE
- CWE-835
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