SB20260919157 - Improper Validation of Specified Quantity in Input in Linux kernel sched



SB20260919157 - Improper Validation of Specified Quantity in Input in Linux kernel sched

Published: September 19, 2026

Security Bulletin ID SB20260919157
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) Improper Validation of Specified Quantity in Input (CVE-ID: CVE-2026-90058)

CWE-ID: CWE-1284 - Improper Validation of Specified Quantity in Input

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.

The vulnerability exists due to improper validation of user-supplied size table values in __qdisc_calculate_pkt_len() when processing a crafted TCA_STAB configuration that amplifies packet length values. A local user can configure a DRR or ETS qdisc with a crafted size table, set a tiny quantum, and send a small packet to cause a denial of service.

The issue requires NET_SCHED and either the DRR or ETS scheduler to be enabled.


Remediation

Install update from vendor's website.