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🛡️ CVE-2022-0547 — debian-linux

🔴 CVSS 9.8 — Critical ✅ No Known Exploit CWE-305 NVD
9.8
CVSS Score
0 Low4 Medium7 High9 Critical10

Description

OpenVPN 2.1 until v2.4.12 and v2.5.6 may enable authentication bypass in external authentication plug-ins when more than one of them makes use of deferred authentication replies, which allows an external user to be granted access with only partially correct credentials.

How this vulnerability can be exploited

This issue can be reached over the network, attack complexity is low, an attacker needs no privileges on the target. No user interaction is required. The scope is unchanged, so the impact stays within the vulnerable component. Rated impact: confidentiality high, integrity high, availability high.

CVSS metrics in full

The score comes from this vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

  • Attack vector: Network — reachable from anywhere that can route to the service.
  • Attack complexity: Low — the attack works reliably, with no preparation.
  • Privileges required: None — an unauthenticated stranger can try it.
  • User interaction: None — nobody has to be tricked into anything.
  • Scope: Unchanged — the damage stays inside the vulnerable component.
  • Confidentiality impact: High — total loss, or loss the attacker controls.
  • Integrity impact: High — total loss, or loss the attacker controls.
  • Availability impact: High — total loss, or loss the attacker controls.

Weakness class

CVE-2022-0547 is classified as CWE-305: Authentication Bypass by Primary Weakness. The authentication algorithm is sound, but the implemented mechanism can be bypassed as the result of a separate weakness that is primary to the authentication error.

Affected software

CVE-2022-0547 is recorded against 3 packages.

  • debian-linux
  • fedora
  • openvpn (from 2.5.0 up to 2.5.6)

Timeline and source

Published on 18 March 2022 and last revised on 17 June 2026. No public exploit is currently recorded for this entry. A vendor advisory or fix has been published. Record sourced from NVD.

References

community.openvpn.net
community.openvpn.net
lists.debian.org
lists.fedoraproject.org
lists.fedoraproject.org
openvpn.net
community.openvpn.net
community.openvpn.net
lists.debian.org
lists.debian.org
lists.fedoraproject.org
lists.fedoraproject.org
openvpn.net

Other advisories for this package

debian-linux has other advisories on record. If you are patching this one, these are worth checking on the same host:

Same weakness in other software

These advisories are the same class of weakness (CWE-305: Authentication Bypass by Primary Weakness) in other software:

CVE-2022-0547 on other distributions

Each distribution ships its own build and its own fixed version. Pick the one you run:

Details

Severity CRITICAL
CVSS Score 9.8
CVSS Vector CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
CWE CWE-305
Public Exploit ✅ No
Source NVD
Published 2022-03-18
Updated 2026-08-20
Modified 2026-06-17

Affected Packages

Software From version Fixed in
debian-linux — —
fedora — —
openvpn 2.5.0 2.5.6

References

Similar Threats

Exploit Protection

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ⓘ Data Notice: The information presented above has been compiled from publicly available internet sources. Boteraser aggregates this data solely for informational purposes and does not independently classify, evaluate, or endorse any findings about the vulnerabilities listed. The accuracy and completeness of this information is the sole responsibility of the original publishers. Boteraser and its operators accept no liability for any decisions made based on this data.

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