CVE-2021-3547

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Published Jul 12, 2021 CVSS 3.1 · 7.4 High EPSS 1.2% KEV · Not listed

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.

Affected Products

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 solution or workaround provided in the CVE record

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.

Metrics

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.

Exploit prediction score: 1.2% (1.238% probability within 30 days)

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

Weaknesses

Sources

CVE record Updated: Aug 3, 2024, 5:01 PM

Status: PUBLISHED
Assigner: OpenVPN
Published: Jul 12, 2021, 10:35 AM
Updated: Aug 3, 2024, 5:01 PM
Reserved: May 11, 2021, 12:00 AM

View source JSON

Vulnrichment No data

No data.

NVD Updated: Jun 17, 2026, 4:05 AM

Status: Modified
Published: Jul 12, 2021, 11:15 AM
Modified: Jun 17, 2026, 4:05 AM

View source JSON

Red Hat No data

No data.

OpenCVE enrichment No data

No data.

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