CVE-2026-11834Public exploit

Root command execution via unsanitized DHCP Option 66

Published Jun 22, 2026 · Updated Jun 22, 2026

OS command injection in affected TP-Link routers allows remote attackers on the WAN broadcast domain to execute commands as root. The Option 66 value from a DHCP lease is concatenated without neutralization into tftp command strings in libcmm.so and passed through util_execSystem() to system(). The router must be a DHCP client on the attacker's broadcast domain, typically while factory-default or unconfigured; no authentication or user interaction is required.

CVSS severity8.7
High
EPSS probability0.66%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

OS command injection in affected TP-Link routers allows remote attackers on the WAN broadcast domain to execute commands as root. The Option 66 value from a DHCP lease is concatenated without neutralization into tftp command strings in libcmm.so and passed through util_execSystem() to system(). The router must be a DHCP client on the attacker's broadcast domain, typically while factory-default or unconfigured; no authentication or user interaction is required.

The record

CVE
CVE-2026-11834
Published
Jun 22, 2026
Updated
Jun 22, 2026
Vendor
TP-Link Systems Inc.
Product
Archer VR2100
Classifications
CWE-78, T1059.004
Attack vector
adjacent
Privileges
unauthenticated

Timeline

How it unfolded

  1. Jun 22, 2026CVE publishedPublication date reported by the CVE source.
  2. Jun 22, 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=0 <EU_V1_260330

What conditions does exploitation require?

Attack vectoradjacent
Required privilegesunauthenticated

What is affected?

TP-Link Systems Inc. · Archer VR2100version=0 <EU_V1_260330
TP-Link Systems Inc. · TL-MR6400version=0 <1.7.0 Build 260413
TP-Link Systems Inc. · Archer MR200version=0 <1.3.0 Build 250605; version=0 <1.5.0 Build 260605
TP-Link Systems Inc. · Archer MR402version=0 <1.5.0 Build 260605
TP-Link Systems Inc. · Archer C20version=0 <EU_V5_260317; version=0 <US_V5_260419; version=0 <V6_260608

Published CVSS scores

8.7TP-LinkCVSS:4.0/AV:A/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA: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)
Vectoradjacent
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitPublished

Weakness, pattern, technique

CWE-78Improper Neutralization of Special Elements used in an OS Command ('OS Command Injection')
T1059.004Command and Scripting Interpreter: Unix Shell

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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