CVE-2026-67279
SSH Pre-Authentication Rekey State Bypass in MikroTik RouterOS
CVSS Score
0.0
EPSS Score
0.0%
EPSS Percentile
0th
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)
| CWE | CWE-841 |
| Vendor | mikrotik |
| Product | routeros |
| Published | Sep 5, 2026 |
| Last Updated | Sep 8, 2026 |
Stay Ahead of the Next One
Get instant alerts for mikrotik routeros
Be the first to know when new unknown vulnerabilities affecting mikrotik routeros are published — delivered to Slack, Telegram or Discord.
Get Free Alerts →
Free · No credit card · 60 sec setup
Affected Versions
Mikrotik / RouterOS
7.24 < 7.24.2 7.0.0 < 7.23.4 6.0.0 < 6.49.21
References
cert.pl: https://cert.pl/en/posts/2026/09/mikrotik-routeros-cve cert.pl: https://cert.pl/en/posts/2026/09/vulnerabilities-in-mikrotik-routeros-actively-exploited/ npratley.net: https://npratley.net/reversing-mikrotiks-silent-patch-the-routeros-7-23-4-fix-they-wouldnt-explain/ mikrotik.com: https://mikrotik.com/supportsec/september-2026-vulnerability/ forum.mikrotik.com: https://forum.mikrotik.com/t/6-49-21-long-term-is-released/272802 forum.mikrotik.com: https://forum.mikrotik.com/t/7-23-4-long-term-is-released/272801 forum.mikrotik.com: https://forum.mikrotik.com/t/7-24-2-stable-is-released/272800
Credits
Sławomir Rozbicki (CERT.PL)