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[ CVE-2026-86060 · Published 5 Sep 2026 ]

MikroTik RouterOS Improper Neutralization of Argument Delimiters in a Command Vulnerability

Exploited · CISA KEV CVSS 9.8 EPSS 6%No fix listed yet

[ Why it matters ]Priority signals

  • Exploited in the wild: on CISA's Known Exploited Vulnerabilities list since 2026-09-10
  • Critical severity: CVSS 9.8

[ Description ]Official description

RouterOS contains an argument-handling flaw in the SSH login path involving usernames that begin with a prohibited character, allowing for the trusted RouterOS policy mask to be changed, leading to privilege escalation. Exploitation requires an unauthenticated SSH session to reach the RouterOS login helper.This issue was fixed in versions: 6.49.21 (Long-term), 7.23.4 (Long-term) and 7.24.2 (Stable)

CISA: MikroTik RouterOS contains an improper neutralization of argument delimiters in a command vulnerability which allows an attacker to change the trusted RouterOS policy mask, leading to privilege escalation.

[ Fixes ]Fixes and patches

CISA required action (US federal deadline 13 Sep 2026): Apply mitigations in accordance with vendor instructions, ensuring compliance with CISA’s BOD 26-04 Prioritizing Security Updates Based on Risk (see URL in Notes) guidance and CISA’s “Forensics Triage Requirements” (see URL in Notes). Follow applicable BOD 26-04 guidance for cloud services or discontinue use of the product if mitigations are unavailable. Stakeholders are responsible for evaluating each asset's internet exposure and ensuring adherence to BOD 26-04 patching guidelines.

No fix or interim patch is linked from our sources yet. Check the vendor references below and limit exposure of affected systems until a fix is available.

[ References ]References