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)

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)

This plugin only works with Tenable.ot.
Please visit https://www.tenable.com/products/tenable-ot for more information.

According to its self-reported version, the remote networking device is running a version of MikroTik RouterOS 7.9 prior to 7.23.4, or 7.24.x prior to 7.24.2. It is, therefore, affected by an authentication bypass 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 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. (CVE-2026-67276)

Note that Nessus has not tested for this issue but has instead relied only on the router's self-reported version number.

ID	Name	Product	Family	Type	Severity
506060	MikroTik RouterOS Improper Verification of Cryptographic Signature (CVE-2026-67276)	Tenable OT Security	Tenable.ot	Remote	critical
344589	MikroTik RouterOS 7.9 < 7.23.4 / 7.24.x < 7.24.2 SSH Authentication Bypass (CVE-2026-67276)	Nessus	Misc.	Remote	critical

Detections

Analytics

CVE-2026-67276

critical

Tenable Plugins

critical

critical