CVE-2025-13943Network attack vector

Authenticated OS command execution via log download

Published Feb 24, 2026 · Updated Feb 24, 2026

Command injection in Zyxel EX3301-T0 firmware 5.50(ABVY.7)C0 and earlier allows remote authenticated users to execute OS commands. The log file download function passes attacker-controlled request data into an OS command without adequate neutralization; Zyxel has not disclosed the parameter or code path. Exploitation requires compromised user-configured credentials, and WAN management is disabled by default.

CVSS severity8.8
High
EPSS probability1.40%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Command injection in Zyxel EX3301-T0 firmware 5.50(ABVY.7)C0 and earlier allows remote authenticated users to execute OS commands. The log file download function passes attacker-controlled request data into an OS command without adequate neutralization; Zyxel has not disclosed the parameter or code path. Exploitation requires compromised user-configured credentials, and WAN management is disabled by default.

The record

CVE
CVE-2025-13943
Published
Feb 24, 2026
Updated
Feb 24, 2026
Vendor
Zyxel Networks
Product
EX3301-T0 firmware
Classifications
CWE-78, T1059
Attack vector
network
Privileges
authenticated

Timeline

How it unfolded

  1. Feb 24, 2026CVE publishedPublication date reported by the CVE source.
  2. Feb 24, 2026Record 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=<= 5.50(ABVY.7)C0

What conditions does exploitation require?

Attack vectornetwork
Required privilegesauthenticated

What is affected?

Zyxel Networks · EX3301-T0 firmwareversion=<= 5.50(ABVY.7)C0

Published CVSS scores

8.8Zyxel CorporationCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

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-78Improper Neutralization of Special Elements used in an OS Command ('OS Command Injection')
T1059Command and Scripting Interpreter

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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