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)
Affected products
Version statuses are supplied by the assigning organization. Consult the original record for detailed ranges and platform conditions.
Mikrotik RouterOS
Default version status: unaffected
7.24 to < 7.24.2affected7.0.0 to < 7.23.4affected6.0.0 to < 6.49.21affected
References
- https://cert.pl/en/posts/2026/09/mikrotik-routeros-cve ↗
- https://cert.pl/en/posts/2026/09/vulnerabilities-in-mikrotik-routeros-actively-exploited/ ↗
- https://npratley.net/reversing-mikrotiks-silent-patch-the-routeros-7-23-4-fix-they-wouldnt-explain/ ↗
- https://mikrotik.com/supportsec/september-2026-vulnerability/ ↗
- https://forum.mikrotik.com/t/6-49-21-long-term-is-released/272802 ↗
- https://forum.mikrotik.com/t/7-23-4-long-term-is-released/272801 ↗
- https://forum.mikrotik.com/t/7-24-2-stable-is-released/272800 ↗
- https://bishopfox.com/blog/mikrotrick-inside-the-routeros-takeover-chain ↗
- https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2026-67279 ↗