SB20260919139 - Use-after-free in Linux kernel sched



SB20260919139 - Use-after-free in Linux kernel sched

Published: September 19, 2026

Security Bulletin ID SB20260919139
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) Use-after-free (CVE-ID: CVE-2026-90071)

CWE-ID: CWE-416 - Use After Free

CVSSv4: 2 [CVSS:4.0/AV:L/AC:L/AT:P/PR:L/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N]


The vulnerability allows a local user to trigger a use-after-free.

The vulnerability exists due to failure to restore the skb->dev device pointer in the sch_teql TEQL scheduler when transmitting packets through TEQL slave devices. A local user can cause a packet to retain a stale device pointer after a slave transmission failure.

Exploitation requires a later slave device without a resolved neighbour and deletion of the previous slave while the packet remains queued.


Remediation

Install update from vendor's website.