CVE-2023-5650

Registration-page URL modification via ZySH privilege flaw

Published Nov 28, 2023 · Updated Aug 2, 2024

Improper privilege management in affected Zyxel firewall firmware allows local users to modify the web GUI registration-page URL. Zyxel identifies ZySH as the affected component but does not disclose the command, authorization check, or unsafe operation that permits the change. Exploitation requires an authenticated local account; the published impact is limited to altering the registration-page destination.

CVSS severity5.5
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

Improper privilege management in affected Zyxel firewall firmware allows local users to modify the web GUI registration-page URL. Zyxel identifies ZySH as the affected component but does not disclose the command, authorization check, or unsafe operation that permits the change. Exploitation requires an authenticated local account; the published impact is limited to altering the registration-page destination.

The record

CVE
CVE-2023-5650
Published
Nov 28, 2023
Updated
Aug 2, 2024
Vendor
Zyxel Networks
Product
Zyxel USG FLEX 50(W) Series Firmware
Classifications
CWE-269, T1565.001
Attack vector
local
Privileges
authenticated

Timeline

How it unfolded

  1. Nov 28, 2023CVE 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=versions 4.16 through 5.37

What conditions does exploitation require?

Attack vectorlocal
Required privilegesauthenticated

What is affected?

Zyxel Networks · Zyxel USG FLEX 50(W) Series Firmwareversion=versions 4.16 through 5.37
Zyxel Networks · Zyxel ATP Series Firmwareversion=versions 4.32 through 5.37
Zyxel Networks · Zyxel USG20(W)-VPN Series Firmwareversion=versions 4.16 through 5.37
Zyxel Networks · Zyxel VPN Series Firmwareversion=versions 4.30 through 5.37
Zyxel Networks · Zyxel USG FLEX Series Firmwareversion=versions 4.50 through 5.37

Published CVSS scores

5.5Zyxel CorporationCVSS:3.1/AV:L/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)
Vectorlocal
Privilegesauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-269Improper Privilege Management
T1565.001Stored Data Manipulation

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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