SB20260916141 - NULL pointer dereference in Linux kernel mm
Published: September 16, 2026
Security Bulletin ID
SB20260916141
CSH Severity
Low
Patch available
YES
Number of vulnerabilities
1
Exploitation vector
Local access
Highest impact
Denial of service
Breakdown by Severity
- Low
- Medium
- High
- Critical
Description
This security bulletin contains information about 1 vulnerability.
1) NULL pointer dereference (CVE-ID: CVE-2026-89966)
CWE-ID: CWE-476 - NULL Pointer Dereference
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 a null pointer dereference in hugetlb_cma_alloc_frozen_folio() when processing gigantic hugepage allocations with MPOL_PREFERRED_MANY. A local user can request a gigantic hugepage allocation and trigger a page fault to cause a denial of service.
Exploitation requires CMA to be configured on only a subset of NUMA nodes.
Remediation
Install update from vendor's website.