SB20261022206 - Reachable assertion in Linux kernel sched



SB20261022206 - Reachable assertion in Linux kernel sched

Published: October 22, 2026

Security Bulletin ID SB20261022206
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) Reachable assertion (CVE-ID: CVE-2026-98622)

CWE-ID: CWE-617 - Reachable Assertion

CVSSv4: 6.8 [CVSS:4.0/AV:L/AC:L/AT:N/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 by triggering a kernel panic.

The vulnerability exists due to a reachable warning assertion in tcf_ct_flow_table_add() in net/sched/act_ct.c when flow_offload_alloc() returns NULL during packet processing through a tc action ct commit classifier. A local user can race a conntrack flush against traffic handled by the classifier to trigger a warning on an expected allocation failure and cause a kernel panic.

The kernel panic requires panic_on_warn=1.


Remediation

Install update from vendor's website.