CVE-2025-3908

Directory exposure via root symlink following

Published May 19, 2025 · Updated May 20, 2025

Link following in OpenVPN 3 Linux 20 through 24 allows local users to expose an arbitrary directory when init-config runs as root. The openvpn3-admin init-config tool follows symbolic links while changing ownership and permissions on two directories used by the D-Bus services. Exploitation requires a prepared local symlink before root executes the tool, after which the target directory can become accessible to unintended users.

CVSS severity6.2
Medium
EPSS probability0.21%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Link following in OpenVPN 3 Linux 20 through 24 allows local users to expose an arbitrary directory when init-config runs as root. The openvpn3-admin init-config tool follows symbolic links while changing ownership and permissions on two directories used by the D-Bus services. Exploitation requires a prepared local symlink before root executes the tool, after which the target directory can become accessible to unintended users.

The record

CVE
CVE-2025-3908
Published
May 19, 2025
Updated
May 20, 2025
Vendor
OpenVPN Inc.
Product
OpenVPN 3 Linux
Classifications
CWE-59, T1222.002
Attack vector
local
Privileges
unauthenticated

Timeline

How it unfolded

  1. May 19, 2025CVE publishedPublication date reported by the CVE source.
  2. May 20, 2025Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

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  1. Affected versionversion=v20 <=v24

What conditions does exploitation require?

Attack vectorlocal
Required privilegesunauthenticated

What is affected?

OpenVPN Inc. · OpenVPN 3 Linuxversion=v20 <=v24

Published CVSS scores

6.2CISA-ADPCVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

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No observations available

Sep 9, 2026Sep 15, 2026
Latest reporting daySep 15, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectorlocal
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-59Improper Link Resolution Before File Access ('Link Following')
T1222.002Linux and Mac File and Directory Permissions Modification

Public exploit references

No public exploit references are available in this record.

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Technologies

Your stack

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Your stack

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