Mikrotik RouterOS up to 7.20.x certificate validation

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
Our Cyber Threat Intelligence team is monitoring different web sites, mailing lists, exploit markets and social media networks. The CTI Interest Score identifies the interest of attackers and the security community for this specific vulnerability in real-time. A high score indicates an elevated risk to be targeted for this vulnerability.
6.9$0-$5k0.00

Summaryinfo

A vulnerability classified as critical has been found in Mikrotik RouterOS up to 7.20.x. Affected is an unknown function. This manipulation causes certificate validation. The identification of this vulnerability is CVE-2025-42611. It is possible to initiate the attack remotely. There is no exploit available.

Detailsinfo

A vulnerability has been found in Mikrotik RouterOS up to 7.20.x and classified as critical. Affected by this vulnerability is some unknown processing. The manipulation with an unknown input leads to a certificate validation vulnerability. The CWE definition for the vulnerability is CWE-295. The product does not validate, or incorrectly validates, a certificate. As an impact it is known to affect confidentiality, integrity, and availability. The summary by CVE is:

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.

The advisory is shared at cert.si. This vulnerability is known as CVE-2025-42611 since 04/16/2025. The exploitation appears to be easy. The attack can be launched remotely. The exploitation doesn't need any form of authentication. Neither technical details nor an exploit are publicly available. The price for an exploit might be around USD $0-$5k at the moment (estimation calculated on 05/09/2026). MITRE ATT&CK project uses the attack technique T1587.003 for this issue.

The vulnerability scanner Nessus provides a plugin with the ID 313232 (MikroTik RouterOS <= 7.20 Authentication Bypass via Improper Certificate Validation (CVE-2025-42611)), which helps to determine the existence of the flaw in a target environment.

There is no information about possible countermeasures known. It may be suggested to replace the affected object with an alternative product.

The vulnerability is also documented in the vulnerability database at Tenable (313232). Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

Productinfo

Type

Vendor

Name

Version

License

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 6.9
VulDB Meta Temp Score: 6.9

VulDB Base Score: 7.3
VulDB Temp Score: 7.3
VulDB Vector: 🔒
VulDB Reliability: 🔍

CNA Base Score: 6.5
CNA Vector (ENISA): 🔒

CVSSv2info

AVACAuCIA
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💳💳💳💳💳💳
💳💳💳💳💳💳
VectorComplexityAuthenticationConfidentialityIntegrityAvailability
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VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍

Exploitinginfo

Class: Certificate validation
CWE: CWE-295 / CWE-287
CAPEC: 🔒
ATT&CK: 🔒

Physical: No
Local: No
Remote: Yes

Availability: 🔒
Status: Not defined

EPSS Score: 🔒
EPSS Percentile: 🔒

Price Prediction: 🔍
Current Price Estimation: 🔒

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Nessus ID: 313232
Nessus Name: MikroTik RouterOS <= 7.20 Authentication Bypass via Improper Certificate Validation (CVE-2025-42611)

Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: no mitigation known
Status: 🔍

0-Day Time: 🔒

Timelineinfo

04/16/2025 CVE reserved
05/05/2026 +384 days Advisory disclosed
05/05/2026 +0 days VulDB entry created
05/09/2026 +4 days VulDB entry last update

Sourcesinfo

Advisory: cert.si
Status: Not defined

CVE: CVE-2025-42611 (🔒)
GCVE (CVE): GCVE-0-2025-42611
GCVE (VulDB): GCVE-100-361129

Entryinfo

Created: 05/05/2026 13:28
Updated: 05/09/2026 04:56
Changes: 05/05/2026 13:28 (62), 05/09/2026 04:56 (2)
Complete: 🔍
Cache ID: 216::103

Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

Discussion

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