Integer overflow in Linux kernel - CVE-2026-68099
Published: August 12, 2026
Vulnerability details
The vulnerability allows a remote attacker to cause a denial of service.
The vulnerability exists due to an integer overflow leading to out-of-bounds reads in ksmbd DACL builders when processing ACL entries. A remote attacker can send data that causes malformed ACL construction to cause a denial of service.
The issue occurs because an overflowed size value is consumed after loop termination, causing the committed NT ACL to under-report the bytes written and become malformed when re-parsed by clients or ksmbd itself.
Affected software
Ubuntu
linux-gcp-7.0 (Ubuntu package)
linux-azure-7.0 (Ubuntu package)
How to mitigate CVE-2026-68099
linux-gcp-7.0 (Ubuntu package) - addressed in versions 7.0.0-38.38~24.04.4, 7.0.0-1013.13~24.04.1, 7.0.0-1014.14~24.04.1
linux-azure-7.0 (Ubuntu package) - addressed in versions 7.0.0-1016.16~24.04.1, 7.0.0-1017.17~24.04.1
External References
- https://git.kernel.org/stable/c/0bf38372821b1526f31538a7d9811844c55c7f38
- https://git.kernel.org/stable/c/847ecd4eb3c117c3d2f13f1e7ab506543aad8183
- https://git.kernel.org/stable/c/bbf0a8e931204ecdab494a88d43b0a24a04285c5
- https://git.kernel.org/stable/c/bc90144ce8bb7fcf05ad9417c7adb4e9509d9e13
- https://git.kernel.org/stable/c/f4fcd0c1a243d449307b887fafee23921e9db5ab