Out-of-bounds write in ImageSharp - #VU150205
Published: September 16, 2026
Vulnerability identifier: #VU150205
CSH Severity: Medium
CVSS v4: 8.7 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N]
CVE-ID: N/A
CWE-ID: CWE-787
Exploitation vector: Remote access
Exploit availability:
No public exploit available
Vulnerability details
The vulnerability allows a remote attacker to cause a denial of service.
The vulnerability exists due to an out-of-bounds write in T6BitCompressor.WriteCode when encoding a 1-bit TIFF image with CCITT Group 4 compression. A remote attacker can supply a crafted Group 4 TIFF that is decoded and re-encoded to cause a denial of service.
The issue is limited to the T6 encoder path.
Affected software
ImageSharp
Remediation
Install security update from vendor's website.
ImageSharp - update to 4.1.2