How severe is CVE-2018-10066?

CVE-2018-10066 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-2018-10066 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (60th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2018-10066?

CVE-2018-10066 affects Mikrotik Routeros. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2018-10066?

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-2018-10066 published?

CVE-2018-10066 was published on 2018-04-13 and last updated on 2026-06-17.

CVE-2018-10066

CVE-2018-10066 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-295.

Key facts

Severity: High (CVSS 3.x base score 8.1)
CVSS v2: 6.8
EPSS exploit prediction: 1% (60th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-295
Affected product: Mikrotik Routeros
Published: 2018-04-13
Last modified: 2026-06-17

Description

An issue was discovered in MikroTik RouterOS 6.41.4. Missing OpenVPN server certificate verification allows a remote unauthenticated attacker capable of intercepting client traffic to act as a malicious OpenVPN server. This may allow the attacker to gain access to the client's internal network (for example, at site-to-site tunnels).

Frequently asked questions

What is CVE-2018-10066?: An issue was discovered in MikroTik RouterOS 6.41.4. Missing OpenVPN server certificate verification allows a remote unauthenticated attacker capable of intercepting client traffic to act as a malicious OpenVPN server. This may allow the attacker to gain access to the client's internal network (for example, at site-to-site tunnels).
How severe is CVE-2018-10066?: CVE-2018-10066 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-2018-10066 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (60th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2018-10066?: CVE-2018-10066 affects Mikrotik Routeros. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2018-10066?: 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-2018-10066 published?: CVE-2018-10066 was published on 2018-04-13 and last updated on 2026-06-17.

References

https://janis-streib.de/2018/04/11/mikrotik-openvpn-security

Affected products (1)

cpe:2.3:a:mikrotik:routeros:6.41.4:*:*:*:*:*:*:*

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