CVE-2025-42611: mikrotik routeros Improper Certificate Validation
Vulnerability summary
CVE-2025-42611 is a medium (CVSS 6.5) Improper Certificate Validation vulnerability in mikrotik routeros. EPSS estimates a 0.19% chance of exploitation in the next 30 days, higher than 7.7% of scored vulnerabilities.
Timeline
- 05-05-2026PublishedVulnerability first disclosed.
- 05-05-2026Last modifiedVulnerability information updated.
Description
RouterOS provides various services that rely on correct verification of client and server certificates to secure confidentiality and integrity of communications. This includes OpenVPN, CAPsMAN, Dot1x (802.1X), among others. The vulnerability lies in shared certificate validation logic which uses the system certificate store that is shared and equally trusted by all system services. This causes confusion of scope, allowing any certificate authority present in the system-wide trust store to be trusted in any context (with some exceptions), allowing partial or full authentication bypass in CAPsMAN, OpenVPN, Dot1X and potentially others.
CVSS metrics
2 scores · 2 sources · 1 version- NVDNIST6.5MediumCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N
EPSS trend
Probability
0.19%
Chance of exploitation in the next 30 days
Percentile
8%
Versus all other CVEs
30-day change
0.00 pp
From 0.19% on 20-09-2026
Known exploited
Compare KEV catalogsNot in any of the 3 tracked catalogs.
Public exploits
0 foundNo public exploits indexed.
Weaknesses
CWE · root causeAffected systems
Mikrotik1 product
- routeros≤ 7.20.x
1 vendor · 1 product