SB20261103129 - Infinite loop in Linux kernel hv driver



SB20261103129 - Infinite loop in Linux kernel hv driver

Published: November 3, 2026

Security Bulletin ID SB20261103129
CSH Severity
Low
Patch available
YES
Number of vulnerabilities 1
Exploitation vector Local access
Highest impact Denial of service

Breakdown by Severity

Low 100%
  • Low
  • Medium
  • High
  • Critical

Description

This security bulletin contains information about 1 vulnerability.


1) Infinite loop (CVE-ID: CVE-2026-99251)

CWE-ID: CWE-835 - Loop with Unreachable Exit Condition ('Infinite Loop')

CVSSv4: 5.7 [CVSS:4.0/AV:L/AC:L/AT:P/PR:L/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N]


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

The vulnerability exists due to an infinite retry loop in the Linux kernel Hyper-V driver's init_vp_index() function when selecting CPUs from a NUMA node that has no CPU in the HK_TYPE_MANAGED_IRQ housekeeping cpumask. A local user can trigger the affected channel initialization path under this CPU configuration to cause a denial of service.


Remediation

Install update from vendor's website.