CVE-2026-67278

MikroTik RouterOS accepts malformed RSA/PKCS#1 v1.5 signatures during X.509 validation. Because its trust store includes an e=3 root CA, an attacker controlling or redirecting an outbound RouterOS TLS connection can use the root’s public certificate - without its private key - to forge a trusted intermediate and issue certificates for arbitrary hostnames, enabling TLS server impersonation. This issue affects only 7.x branch was fixed in versions: 7.23.4 (Long-term) and 7.24.2 (Stable)

CVSS

No CVSS.

References

Link	Resource
https://cert.pl/en/posts/2026/09/mikrotik-routeros-cve
https://cert.pl/en/posts/2026/09/vulnerabilities-in-mikrotik-routeros-actively-exploited/
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-they-wouldnt-explain/

Configurations

No configuration.

History

No history.

Information

Published : 2026-09-05 20:17

Updated : 2026-09-08 16:18

NVD link : CVE-2026-67278

Mitre link : CVE-2026-67278

CVE.ORG link : CVE-2026-67278

JSON object : View

Products Affected

No product.

CWE

CWE-347

Improper Verification of Cryptographic Signature

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