How severe is CVE-2026-67276?

CVE-2026-67276 has a CVSS 3.x base score of 8.1, rated high severity. It is exploitable over network with high attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2026-67276 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 6% (94th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2026-67276?

CVE-2026-67276 affects Mikrotik Routeros. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2026-67276?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.

When was CVE-2026-67276 published?

CVE-2026-67276 was published on 2026-09-05 and last updated on 2026-09-25.

CVE-2026-67276

CVE-2026-67276 is a high-severity vulnerability in Mikrotik Routeros with a CVSS 3.x base score of 8.1. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-347.

Key facts

Severity: High (CVSS 3.x base score 8.1)
CVSS v4: 9.2
EPSS exploit prediction: 6% (94th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-347
Affected product: Mikrotik Routeros
Published: 2026-09-05
Last modified: 2026-09-25

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)

Frequently asked questions

What is CVE-2026-67276?: 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)
How severe is CVE-2026-67276?: CVE-2026-67276 has a CVSS 3.x base score of 8.1, rated high severity. It is exploitable over network with high attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2026-67276 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 6% (94th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2026-67276?: CVE-2026-67276 affects Mikrotik Routeros. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2026-67276?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
When was CVE-2026-67276 published?: CVE-2026-67276 was published on 2026-09-05 and last updated on 2026-09-25.

References

Affected products (1)

cpe:2.3:o:mikrotik:routeros:*:*:*:*:*:*:*:*

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