MikroTik RouterOS accepts malformed RSA/PKCS#1 v1.5 signatures across RSA-based services, including TLS/X.509 certificate validation and SSH host-key authentication. Because its trust store includes …
Critical CVSS 9.1
Summary
MikroTik RouterOS accepts malformed RSA/PKCS#1 v1.5 signatures across RSA-based services, including TLS/X.509 certificate validation and SSH host-key authentication. 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. The same permissive verifica…
In-depth triage
No in-depth report has been generated yet (DR-003 v2 AI pipeline is under construction).
Affected products
- :
Sources
- NVD DATABASE
- Grok bot vulnerability crawler DATABASE
Original Links
- 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/7-23-6-long-term-is-released/273139
- https://forum.mikrotik.com/t/7-24-3-stable-is-released/273138
- https://mikrotik.com/supportsec/september-2026-vulnerability/
- https://npratley.net/reversing-mikrotiks-silent-patch-the-routeros-7-23-4-fix-they-wouldnt-explain/
Timeline
- nvd_ingest NVD
- grok_bot_ingest Grok bot vulnerability crawler