SB20261015146 - Division by zero in Linux kernel x86 kernel

Description

This security bulletin contains information about 1 vulnerability.

1) Division by zero (CVE-ID: CVE-2026-98390)

CWE-ID: CWE-369 - Divide By Zero

CVSSv4: 0 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:N/SC:N/SI:N/SA:N]

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

The vulnerability exists due to division by zero in the amd_smn_init() function in arch/x86/kernel/amd_node.c when initializing a system whose topology causes roots_per_node to be calculated as zero. A local user can trigger the affected initialization under these topology conditions to cause a denial of service.

The issue has been observed in Xen PVH dom0 with two nodes and one root, but other systems may also be affected.

Remediation

Install update from vendor's website.

References

• https://git.kernel.org/stable/c/72bd92bd8190d7869ecb462649ca40f297822a33
• https://git.kernel.org/stable/c/9273a90465d58b82aca4bea71451ef6bee084928
• https://git.kernel.org/stable/c/94e984d8858a3228952b02f84e66610961098cc2