CVE-2025-21603Network attack vector

Script execution via manipulated device settings

Published Jan 8, 2025 · Updated Jan 8, 2025

Cross-site scripting in PLANEX MZK-DP300N firmware 1.05 and earlier allows remote authenticated users to execute scripts through crafted URLs. Public advisories state that the attacker first manipulates device settings, but they do not identify the affected setting, handler, or missing neutralization operation. Exploitation requires device login and a logged-in user to open the crafted URL; impact is limited to script execution in that user's browser.

CVSS severity4.8
Medium
EPSS probability0.29%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Cross-site scripting in PLANEX MZK-DP300N firmware 1.05 and earlier allows remote authenticated users to execute scripts through crafted URLs. Public advisories state that the attacker first manipulates device settings, but they do not identify the affected setting, handler, or missing neutralization operation. Exploitation requires device login and a logged-in user to open the crafted URL; impact is limited to script execution in that user's browser.

The record

CVE
CVE-2025-21603
Published
Jan 8, 2025
Updated
Jan 8, 2025
Vendor
PLANEX COMMUNICATIONS INC.
Product
MZK-DP300N
Classifications
CWE-79, T1203
Attack vector
network
Privileges
admin

Timeline

How it unfolded

  1. Jan 8, 2025CVE publishedPublication date reported by the CVE source.
  2. Jan 8, 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?

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

  1. Affected versionversion=firmware versions 1.05 and earlier

What conditions does exploitation require?

Attack vectornetwork
Required privilegesadmin

What is affected?

PLANEX COMMUNICATIONS INC. · MZK-DP300Nversion=firmware versions 1.05 and earlier

Published CVSS scores

4.8JPCERT/CCCVSS:3.0/AV:N/AC:L/PR:H/UI:R/S:C/C:L/I:L/A:N
4.8CISA-ADPCVSS:3.1/AV:N/AC:L/PR:H/UI:R/S:C/C:L/I:L/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
Privilegesadmin
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-79Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
T1203Exploitation for Client Execution

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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