CVE-2026-67278Critical· 9.1▾ AbyssalPoC availableMikroTik 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 controllin…
▾ Abyssal zone — Critical with a public exploit or in-the-wild use
impact 50.1 · likelihood 0.1 · exploitation 12
A public proof-of-concept already exists for this vulnerability — see Exploit availability below.
Stakeholder-Specific Vulnerability Categorization from CISA's ADP record at CVE.org: whether exploitation is observed, whether an attack can be automated, and how much of the system is at stake.
Exploit-prediction probability, daily snapshots since Sep 6.
Disclosure to exploitation, from the record and what we observed since indexing it.
Disclosed via NVD
0.2%
Exploit / PoC code exists
— → 6.3
none → medium
6.3 → —
medium → none
— → 6.3
none → medium
Last analysed / modified upstream
0.2% → 0.3%
6.3 → 9.1
medium → critical
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 verification also undermines RSA-based SSH authentication.
This issue affects only 7.x branch was fixed in versions: 7.23.6 (Long-term) and 7.24.3 (Stable). Releases 7.23.4 and 7.24.2 included an incomplete fix.
routeros >= 7.0, < 7.23.6routeros >= 7.24, < 7.24.3Upgrade past the affected range:
routeros 7.24.3Field changes observed since this record was first indexed.
Connected by shared product, vendor, weakness, or advisory.
CVE-2026-67276High· 8.1RouterOS 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
CVE-2026-86060Critical· 9.8RouterOS contains an argument-handling flaw in the SSH login path involving usernames that begin with a prohibited character, allowing for the trusted RouterOS policy mask to be changed, leading to privilege escalation
CVE-2026-67281High· 7.5RouterOS WebFig contains an unauthenticated file-read vulnerability in the /jsproxy path where a newly allocated session retains a stale uninitialized principal pointer used for file authorization
CVE-2026-67279Medium· 6.5RouterOS 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
CVE-2026-67277High· 8.2RouterOS accepts a "related" btest connection before the corresponding primary session has completed authentication
CVE-2026-89020Medium· 4.3MikroTik RouterOS before 7.23.4 (long-term) and 7.24.2 (stable) contains a stack-based buffer overflow vulnerability in the mtget binary's TFTP RRQ builder function that allows authenticated users to crash the mtget worker process by sup…