SB2026102659 - Always-Incorrect Control Flow Implementation in Linux kernel riscv kernel



SB2026102659 - Always-Incorrect Control Flow Implementation in Linux kernel riscv kernel

Published: October 26, 2026

Security Bulletin ID SB2026102659
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) Always-Incorrect Control Flow Implementation (CVE-ID: CVE-2026-99092)

CWE-ID: CWE-670 - Always-Incorrect Control Flow Implementation

CVSSv4: 4.8 [CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N]


The vulnerability allows a local user to cause BPF just-in-time compilation to fail on affected RISC-V systems.

The vulnerability exists due to incorrect configuration-dependent control flow in the RISC-V patch_map() function when copying BPF instructions into read-only executable memory with CONFIG_STRICT_MODULE_RWX disabled. A local user can trigger BPF just-in-time compilation to cause instruction copying to fail because a temporary writable mapping is not created, leaving the BPF program un-JITed.

Builds without MMU support are unaffected.


Remediation

Install update from vendor's website.