Vulnerability Description
RouterOS does not compare the complete RSA public key when matching an SSH authentication request to an authorized user key, checking the key type and modulus but omitting the exponent. Because signature verification uses the client-supplied key, an attacker knowing an authorized RSA modulus can supply a key with exponent one, forge a valid signature, and open an SSH command channel as the target user without the private key.This issue affects only 7.x branch was fixed in versions: 7.23.4 (Long-term) and 7.24.2 (Stable)
Related Weaknesses (CWE)
References
- https://cert.pl/en/posts/2026/09/mikrotik-routeros-cve
- https://cert.pl/en/posts/2026/09/vulnerabilities-in-mikrotik-routeros-actively-e
- 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://mikrotik.com/supportsec/september-2026-vulnerability/
- https://npratley.net/reversing-mikrotiks-silent-patch-the-routeros-7-23-4-fix-th
FAQ
What is CVE-2026-67276?
CVE-2026-67276 is a documented vulnerability. RouterOS does not compare the complete RSA public key when matching an SSH authentication request to an authorized user key, checking the key type and modulus but omitting the exponent. Because signat...
How severe is CVE-2026-67276?
CVSS scoring is not yet available for CVE-2026-67276. Check NVD for updates.
Is there a patch for CVE-2026-67276?
Check the references section above for vendor advisories and patch information. Review vendor security bulletins for remediation guidance.