Heap-based buffer overflow in Linux kernel - CVE-2026-80639

Vulnerability details

The vulnerability allows a local user to cause a denial of service.

The vulnerability exists due to a buffer overflow in setup_xor_mapping() in tools/testing/cxl/test/cxl_translate.c when processing xor mapping data. A local user can trigger the vulnerable code path to cause a denial of service.

The issue occurs in the cxl test code path and results in a runtime fortify panic.

Affected software

How to mitigate CVE-2026-80639

External References

• https://git.kernel.org/stable/c/08326b92c7a414a73b5b308d1daf0e91e0134dfc
• https://git.kernel.org/stable/c/8c4f27a7f364eab514d2fa55c11f39d505122f1b

Related Security Bulletins

• Heap-based buffer overflow in Linux kernel cxl test