CVE-2022-0910Network attack vector

Authenticated VPN access via missing second-factor enforcement

Published May 24, 2022 · Updated Aug 2, 2024

Improper authentication in affected Zyxel firewall firmware allows remote authenticated users to access IPsec VPNs without 2FA. The CGI program lacks proper access control for the second authentication phase and accepts a valid first factor as sufficient. Remote authenticated users need valid account credentials and a reachable IPsec VPN service; exploitation grants VPN access but no reported direct data disclosure or service interruption.

CVSS severity6.5
Medium
EPSS probability0.70%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Improper authentication in affected Zyxel firewall firmware allows remote authenticated users to access IPsec VPNs without 2FA. The CGI program lacks proper access control for the second authentication phase and accepts a valid first factor as sufficient. Remote authenticated users need valid account credentials and a reachable IPsec VPN service; exploitation grants VPN access but no reported direct data disclosure or service interruption.

The record

CVE
CVE-2022-0910
Published
May 24, 2022
Updated
Aug 2, 2024
Vendor
Zyxel Networks
Product
Zyxel ATP Series Firmware
Classifications
CWE-287, T1078
Attack vector
network
Privileges
authenticated

Timeline

How it unfolded

  1. May 24, 2022CVE publishedPublication date reported by the CVE source.
  2. Aug 2, 2024Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=4.32 through 5.21

What conditions does exploitation require?

Attack vectornetwork
Required privilegesauthenticated

What is affected?

Zyxel Networks · Zyxel ATP Series Firmwareversion=4.32 through 5.21
Zyxel Networks · Zyxel ZyWALL/USG Series Firmwareversion=4.32 through 4.71
Zyxel Networks · Zyxel VPN Series Firmwareversion=4.32 through 5.21
Zyxel Networks · Zyxel USG FLEX Series Firmwareversion=4.50 through 5.21

Published CVSS scores

4.0NIST NVDAV:N/AC:L/Au:S/C:N/I:P/A:N
6.5Zyxel CorporationCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:H/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.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-287Improper Authentication
T1078Valid Accounts

Public exploit references

No public exploit references are available in this record.

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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