CVE-2026-7124Public exploitNetwork attack vector

Unauthenticated command execution via addrPrefixLen injection

Published Apr 27, 2026 · Updated Apr 27, 2026

OS command injection in TOTOLINK A8000RU 7.1cu.643_b20200521 allows remote attackers to execute arbitrary commands via addrPrefixLen. The setIpv6LanCfg handler in /cgi-bin/cstecgi.cgi incorporates addrPrefixLen into a string passed through Uci_Set_Str and CsteSystem, which ultimately invokes execv without neutralizing shell metacharacters. No account or user interaction is required, and successful requests execute attacker-chosen commands in the router's firmware context.

CVSS severity9.8
Critical
EPSS probability1.77%
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 TOTOLINK A8000RU 7.1cu.643_b20200521 allows remote attackers to execute arbitrary commands via addrPrefixLen. The setIpv6LanCfg handler in /cgi-bin/cstecgi.cgi incorporates addrPrefixLen into a string passed through Uci_Set_Str and CsteSystem, which ultimately invokes execv without neutralizing shell metacharacters. No account or user interaction is required, and successful requests execute attacker-chosen commands in the router's firmware context.

The record

CVE
CVE-2026-7124
Published
Apr 27, 2026
Updated
Apr 27, 2026
Vendor
TOTOLINK
Product
A8000RU
Classifications
CWE-78, CWE-77, T1059.004, T1190
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Apr 27, 2026CVE publishedPublication date reported by the CVE source.
  2. Apr 27, 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=7.1cu.643_b20200521

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

TOTOLINK · A8000RUversion=7.1cu.643_b20200521

Published CVSS scores

8.9VulDBCVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:P
9.8VulDBCVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
10.0VulDBAV:N/AC:L/Au:N/C:C/I:C/A:C
9.8VulDBCVSS:3.1/AV:N/AC:L/PR:N/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 9, 2026Sep 15, 2026
Latest reporting daySep 15, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitPublished

Weakness, pattern, technique

CWE-78Improper Neutralization of Special Elements used in an OS Command ('OS Command Injection')
CWE-77Improper Neutralization of Special Elements used in a Command ('Command Injection')
T1059.004Unix Shell
T1190Exploit Public-Facing Application

Public exploit references

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

See the directory against your own environment.

Your stack

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