What is CVE-2026-67279?
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)
Timeline
- 2026-09-05Published to the U.S. National Vulnerability Database (NVD)
- 2026-09-24First covered in a defend.network daily briefing
- 2026-09-25Added to the CISA Known Exploited Vulnerabilities (KEV) catalog
- 2026-09-26NVD record last updated
- 2026-09-28CISA federal remediation deadline (BOD 22-01)
CISA Known Exploited Vulnerability
Mikrotik RouterOS Improper Enforcement of Behavioral Workflow Vulnerability
Affected product
MikroTik RouterOS
Remediation Steps
- Apply the vendor security update for MikroTik RouterOS as a priority.
- Restrict network exposure of the affected service to trusted sources until patched.
- Review logs and detections for indicators of exploitation.
- Confirm fixed versions against the official vendor advisory before deploying.
References
- https://mikrotik.com/supportsec/september-2026-vulnerability/
- https://cert.pl/en/posts/2026/09/mikrotik-routeros-cve
- https://cert.pl/en/posts/2026/09/vulnerabilities-in-mikrotik-routeros-actively-exploited/
- https://nvd.nist.gov/vuln/detail/CVE-2026-67279
- https://www.cisa.gov/known-exploited-vulnerabilities-catalog
Referenced in our briefings & reports
- Vulnerability Priority Report – Week 2 of October 2026 (October 12 – 18)
- Vulnerability Priority Report – Week 1 of October 2026 (October 5 – 11)
- Oracle PeopleSoft, Microsoft patches, Elementor RCE under active exploitation (2026-09-27)
- Check Point RCE, MikroTik SSH chain, malicious npm/Terraform packages in active exploitation (2026-09-24)
Related vulnerabilities
- CVE-2026-67277 – MikroTik RouterOS (same product)
- CVE-2026-86060 – MikroTik RouterOS (same product)
Browse all tracked CVEs in the defend.network CVE database →
🤖 This CVE page is generated by defend.network from NVD, CISA KEV, EPSS, and our verified daily briefings. Severity and exploitation data come from official sources; always verify remediation steps against the official vendor advisory before acting in production.