CVE-2026-67279: Mikrotik RouterOS Improper Enforcement of Behavioral Workflow Vulnerability
What it is
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.
What to do
Schedule the vendor fix into this week’s change window, prioritising internet-facing and business-critical systems. Confirm the fix is applied everywhere, not just where it was easy.
- Priority
- This week: Schedule into this week’s change window.
- Severity (CVSS)
- 6.9 medium
- CISA assessment (SSVC)
- actively exploited; attackers can automate it at scale; partial control or data exposure
- Exploit probability (EPSS, 30 days)
- 1.0%, higher than 62% of all CVEs
- Added to CISA KEV
- 25 September 2026
- CISA fix-by date
- 28 September 2026 (US federal agencies; a sensible deadline for everyone)
- Ransomware use
- Not known
- Weakness
- CWE-841
References
- NIST NVD entry
- CISA KEV entry
- cert.pl/en/posts/2026/09/mikrotik-routeros-cve
- cert.pl/en/posts/2026/09/vulnerabilities-in-mikrotik-routeros-actively-exploited
- forum.mikrotik.com/t/6-49-21-long-term-is-released/272802
- forum.mikrotik.com/t/7-23-4-long-term-is-released/272801
- forum.mikrotik.com/t/7-24-2-stable-is-released/272800
- mikrotik.com/supportsec/september-2026-vulnerability/
Sources: CISA Known Exploited Vulnerabilities · FIRST Exploit Prediction Scoring System (EPSS) · NIST National Vulnerability Database · CISA Vulnrichment (SSVC), via the CVE Program. This product uses data from the NVD API but is not endorsed or certified by the NVD. Summaries are machine-written from CISA’s description; treat the vendor’s advisory as the authority for fixes.