CVE-2026-36741Public exploitNetwork attack vector

Authenticated command execution via unsanitized NTP parameter

Published May 13, 2026 · Updated May 13, 2026

Command injection in U-SPEED T18-21K firmware 1.0 allows remote authenticated users to execute system commands through NTP settings. The /api/system/ntp handler processes shell metacharacters in the ntpSrv1 parameter without sanitizing them before operating-system execution. Administrative web access is required, and elevated execution allows reading sensitive files, changing configuration, or interrupting routing.

CVSS severity7.2
High
EPSS probability2.09%
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 U-SPEED T18-21K firmware 1.0 allows remote authenticated users to execute system commands through NTP settings. The /api/system/ntp handler processes shell metacharacters in the ntpSrv1 parameter without sanitizing them before operating-system execution. Administrative web access is required, and elevated execution allows reading sensitive files, changing configuration, or interrupting routing.

The record

CVE
CVE-2026-36741
Published
May 13, 2026
Updated
May 13, 2026
Vendor
Unknown vendor
Product
Unknown product
Classifications
CWE-77, T1059
Attack vector
network
Privileges
admin

Timeline

How it unfolded

  1. May 13, 2026CVE publishedPublication date reported by the CVE source.
  2. May 13, 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?

Affected buildAffected product and version details are unavailable.

What conditions does exploitation require?

Attack vectornetwork
Required privilegesadmin

What is affected?

Affected products and versions are unavailable in this record.

Published CVSS scores

7.2CISA-ADPCVSS:3.1/AV:N/AC:L/PR:H/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.

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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 exploitPublished

Weakness, pattern, technique

CWE-77Improper Neutralization of Special Elements used in a Command ('Command Injection')
T1059Command and Scripting Interpreter

Public exploit references

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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