CVE-2021-3547 - Vulnerability Details - OpenCVE

Description

OpenVPN 3 Core Library version 3.6 and 3.6.1 allows a man-in-the-middle attacker to bypass the certificate authentication by issuing an unrelated server certificate using the same hostname found in the verify-x509-name option in a client configuration.

Published: 2021-07-12

Score: 7.4 High

EPSS: < 1% Very Low

KEV: No

Impact:

Action:

Analysis

Analysis and contextual insights are available on OpenCVE Cloud.

Default status is the baseline for the product, each version can override it (e.g. patched versions marked unaffected).

Vendor Product Default status Versions

n/a

OpenVPN 3 Core Library

affected

Version	Status	Constraints
`3.6 and 3.6.1`	affected	—

Configuration 1 [-]

OR	cpe:2.3:a:openvpn:openvpn:3.6:::::::*
	cpe:2.3:a:openvpn:openvpn:3.6.1:::::::*

No data.

No data available yet.

Remediation

No vendor fix or workaround currently provided.

Additional remediation guidance may be available on OpenCVE Cloud.

Tracking

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Advisories

Source	ID	Title
EUVD	EUVD-2021-26858	OpenVPN 3 Core Library version 3.6 and 3.6.1 allows a man-in-the-middle attacker to bypass the certificate authentication by issuing an unrelated server certificate using the same hostname found in the verify-x509-name option in a client configuration.

No CVSS v4.0

Attack Vector Network

Attack Complexity High

Privileges Required None

Scope Unchanged

Confidentiality Impact High

Integrity Impact High

Availability Impact None

User Interaction None

No CVSS v3.0

Access Vector Network

Access Complexity Medium

Authentication None

Confidentiality Impact Partial

Integrity Impact Partial

Availability Impact None

This CVE is not in the KEV list.

The EPSS score is 0.00037.

Key SSVC decision points have not yet been added.

References

Link	Providers
https://community.openvpn.net/openvpn/wiki/CVE-2021-3547
https://community.openvpn.net/openvpn/wiki/SecurityAnnouncements

History

No history.

Subscriptions

Openvpn Openvpn

MITRE

Status: PUBLISHED

Assigner: OpenVPN

Published: 2021-07-12T10:35:52.000Z

Updated: 2024-08-03T17:01:06.568Z

Reserved: 2021-05-11T00:00:00.000Z

Link: CVE-2021-3547

Vulnrichment

No data.

NVD

Status : Modified

Published: 2021-07-12T11:15:08.233

Modified: 2024-11-21T06:21:48.747

Link: CVE-2021-3547

Redhat

No data.

OpenCVE Enrichment

No data.

Weaknesses

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