CVE-2026-9404: Totolink A8000RU Web Management cstecgi.cgi setDdnsCfg os command injection

Vulnerability summary

CVE-2026-9404 is a high (CVSS 10.0) Command Injection vulnerability in totolink a8000ru_firmware. EPSS estimates a 3.25% chance of exploitation in the next 30 days, higher than 88.2% of scored vulnerabilities. 1 public exploit is recorded.

Timeline

1. 24-05-2026
   PublishedVulnerability first disclosed.
2. 29-05-2026
   Last modifiedVulnerability information updated.

Description

A vulnerability was identified in Totolink A8000RU 7.1cu.643_b20200521. This affects the function setDdnsCfg of the file /cgi-bin/cstecgi.cgi of the component Web Management Interface. Such manipulation of the argument provider leads to os command injection. The attack may be launched remotely. The exploit is publicly available and might be used.

• CWE-77Improper Neutralization of Special Elements used in a Command ('Command Injection')The product constructs all or part of a command using externally-influenced input from an upstream component, but it does not neutralize or incorrectly neutralizes special elements that could modify the intended command when it is sent to a downstream component.
• CWE-78Improper Neutralization of Special Elements used in an OS Command ('OS Command Injection')The product constructs all or part of an OS command using externally-influenced input from an upstream component, but it does not neutralize or incorrectly neutralizes special elements that could modify the intended OS command when it is sent to a downstream component.