SB2026091951 - Off-by-one in Linux kernel core



SB2026091951 - Off-by-one in Linux kernel core

Published: September 19, 2026

Security Bulletin ID SB2026091951
CSH Severity
Low
Patch available
YES
Number of vulnerabilities 1
Exploitation vector Local access
Highest impact Partial DoS

Breakdown by Severity

Low 100%
  • Low
  • Medium
  • High
  • Critical

Description

This security bulletin contains information about 1 vulnerability.


1) Off-by-one (CVE-ID: CVE-2026-90160)

CWE-ID: CWE-193 - Off-by-one Error

CVSSv4: 4.6 [CVSS:4.0/AV:L/AC:L/AT:N/PR:H/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N]


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

The vulnerability exists due to an off-by-one headroom validation error in the lwt_bpf bpf_xmit() path when an LWT_XMIT BPF program modifies skb headroom. A local privileged user can call bpf_skb_change_head() to leave insufficient headroom and cause a denial of service.

On Ethernet, cached hardware-header output requires 16 bytes of headroom although the device hard-header length is 14 bytes.


Remediation

Install update from vendor's website.