[ CVE-2026-67279 · Published 5 Sep 2026 ]
Mikrotik RouterOS Improper Enforcement of Behavioral Workflow Vulnerability
[ Why it matters ]Priority signals
- Exploited in the wild: on CISA's Known Exploited Vulnerabilities list since 2026-09-25
[ Description ]Official description
RouterOS SSH enters the connection protocol after a client-requested rekey even though user authentication was never attempted, allowing an unauthenticated client to open a session channel and send an exec request. On affected builds the server dispatches the command, enabling unauthenticated creation, overwrite, and reconstruction of files in the RouterOS managed file namespace, including support files containing configuration and diagnostic data.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 enforcement of behavioral workflow vulnerability that could allow an unauthenticated client to open a session channel and send an exec request. This vulnerability can be chained to achieve unauthenticated exploitation of CVE-2026-86060.
[ Fixes ]Fixes and patches
CISA required action (US federal deadline 28 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
- cert.pl/en/posts/2026/09/mikrotik-routeros-cveThird Party Advisory
- cert.pl/en/posts/2026/09/vulnerabilities-in-mikrotik-routeros-actively-exploitedMitigationThird Party Advisory
- forum.mikrotik.com/t/6-49-21-long-term-is-released/272802Release Notes
- forum.mikrotik.com/t/7-23-4-long-term-is-released/272801Release Notes
- forum.mikrotik.com/t/7-24-2-stable-is-released/272800Release Notes
- mikrotik.com/supportsec/september-2026-vulnerabilityVendor Advisory
- npratley.net/reversing-mikrotiks-silent-patch-the-routeros-7-23-4-fix-they-wouldnt-explainExploitThird Party Advisory
- bishopfox.com/blog/mikrotrick-inside-the-routeros-takeover-chainThird Party Advisory
- www.cisa.gov/known-exploited-vulnerabilities-catalogUS Government Resource