PT-2021-2690 · Openvpn+5 · Openvpn+5

David Sommerseth

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Published

2021-04-22

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Updated

2024-10-24

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CVE-2020-15078

CVSS v3.1

7.5

High

VectorAV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N
Name of the Vulnerable Software and Affected Versions OpenVPN versions 2.5.1 and earlier
Description The issue allows a remote attacker to bypass authentication and access control channel data on servers configured with deferred authentication. This can potentially be used to trigger further information leaks. The vulnerability is related to the deferred authentication function, which can be exploited to force the server to return a PUSH REPLY message with VPN settings before sending an AUTH FAILED message.
Recommendations For OpenVPN versions 2.5.1 and earlier, update to version 2.5.2 to fix the security vulnerabilities. As a temporary workaround, consider disabling the deferred authentication feature until a patch is available. Restrict access to the control channel to minimize the risk of exploitation. Avoid using the --auth-gen-token option or user-specific token auth solutions in combination with deferred authentication until the issue is resolved.

Fix

Missing Authentication

Weakness Enumeration

CWE-306CWE-305

Related Identifiers

ALT-PU-2021-2120
ALT-PU-2022-1576
ALT-PU-2022-2690
ALT-PU-2024-14147
ALT-PU-2024-14550
ALT-PU-2024-14578
BDU:2021-02221
CVE-2020-15078
DLA-2992-1
MGASA-2021-0302
OESA-2021-1197
OPENSUSE-SU-2021:0734-1
OPENSUSE-SU-2021_0734-1
OPENSUSE-SU-2024:11128-1
SUSE-SU-2021:14723-1
SUSE-SU-2021:1576-1
SUSE-SU-2021:1577-1
SUSE-SU-2021_14723-1
USN-4933-1

Affected Products

Alt Linux
Astra Linux
Linuxmint
Openvpn
Suse
Ubuntu