Cyber Posture

CVE-2026-7123

CriticalRCE

Published: 27 April 2026

Published
27 April 2026
Modified
27 April 2026
KEV Added
Patch
CVSS Score 9.8 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
EPSS Score 0.0125 79.6th percentile
Risk Priority 20 60% EPSS · 20% KEV · 20% CVSS

Summary

CVE-2026-7123 is a critical-severity Command Injection (CWE-77) vulnerability in Totolink A8000RU (inferred from references). Its CVSS base score is 9.8 (Critical).

Operationally, exploitation aligns with the MITRE ATT&CK technique Exploit Public-Facing Application (T1190); ranked in the top 20.4% of CVEs by exploit likelihood; it is not currently listed in the CISA KEV catalog.

The strongest mitigations our analysis identified are NIST 800-53 IA-8 (Identification and Authentication (Non-organizational Users)) and SI-10 (Information Input Validation).

Threat & Defense at a Glance

What attackers do: exploitation maps to Exploit Public-Facing Application (T1190) and 1 other technique. What defenders deploy: see the NIST 800-53 controls recommended below.
Threat & Defense Details

Mitigating Controls (NIST 800-53 r5)AI

prevent

Directly prevents OS command injection by validating and sanitizing the setIptvCfg argument in the vulnerable CGI handler.

prevent

Remediates the specific flaw in the setIptvCfg function of /cgi-bin/cstecgi.cgi through timely patching of the Totolink firmware.

prevent

Requires identification and authentication for non-organizational remote users, blocking unauthenticated exploitation of the vulnerable endpoint.

MITRE ATT&CK Enterprise TechniquesAI

T1190 Exploit Public-Facing Application Initial Access
Adversaries may attempt to exploit a weakness in an Internet-facing host or system to initially access a network.
T1059.008 Network Device CLI Execution
Adversaries may abuse scripting or built-in command line interpreters (CLI) on network devices to execute malicious command and payloads.
Why these techniques?

The vulnerability is an unauthenticated OS command injection in a public-facing router CGI interface, directly enabling initial access via public-facing application exploitation (T1190) and command execution on a network device CLI/web interface (T1059.008).

Confidence: HIGH · MITRE ATT&CK Enterprise v19.0

NVD Description

A vulnerability was found in Totolink A8000RU 7.1cu.643_b20200521. Affected is the function setIptvCfg of the file /cgi-bin/cstecgi.cgi of the component CGI Handler. Performing a manipulation of the argument setIptvCfg results in os command injection. The attack can be initiated remotely.…

more

The exploit has been made public and could be used.

Deeper analysisAI

CVE-2026-7123 is an OS command injection vulnerability (CWE-77, CWE-78) affecting the Totolink A8000RU router on firmware version 7.1cu.643_b20200521. The issue lies in the setIptvCfg function of the /cgi-bin/cstecgi.cgi file within the CGI Handler component. Manipulation of the setIptvCfg argument enables arbitrary OS command execution.

The vulnerability carries a CVSS v3.1 base score of 9.8 (AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H), marking it as critical. Unauthenticated remote attackers can exploit it with low complexity and no user interaction, potentially gaining high-impact control over confidentiality, integrity, and availability of the affected device, such as executing arbitrary commands for full compromise.

References include a GitHub repository with a public exploit at https://github.com/Litengzheng/vuldb_new2/blob/main/A8000RU/vul_308/README.md, VulDB entries at https://vuldb.com/vuln/359722 and https://vuldb.com/submit/800995, and the vendor site at https://www.totolink.net/. No specific mitigation or patch details are provided in the CVE description.

The exploit has been made public and could be used, as stated in the advisory.

Details

CWE(s)

Affected Products

Totolink
A8000RU
inferred from references and description; NVD did not file a CPE for this CVE

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CVE-2026-5997Shared CWE-77, CWE-78
CVE-2026-7153Shared CWE-77, CWE-78
CVE-2026-6138Shared CWE-77, CWE-78

References