CVE-2026-9436: Totolink A8000RU Web Management cstecgi.cgi setL2tpServerCfg os command injection

Vulnerability summary

CVE-2026-9436 is a high (CVSS 10.0) Command Injection vulnerability in totolink a8000ru_firmware. EPSS estimates a 3.46% chance of exploitation in the next 30 days, higher than 88.9% of scored vulnerabilities. 1 public exploit is recorded.

Timeline

1. 25-05-2026
   PublishedVulnerability first disclosed.
2. 28-05-2026
   Last modifiedVulnerability information updated.

Description

A flaw has been found in Totolink A8000RU 7.1cu.643_b20200521. The impacted element is the function setL2tpServerCfg of the file /cgi-bin/cstecgi.cgi of the component Web Management Interface. Executing a manipulation of the argument enable can lead to os command injection. The attack can be executed remotely. The exploit has been published and may 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.