CVE-2026-5103: totolink a3300r_firmware Injection

Vulnerability summary

CVE-2026-5103 is a high (CVSS 8.8) Injection vulnerability in totolink a3300r_firmware. EPSS estimates a 3.55% chance of exploitation in the next 30 days, higher than 89.2% of scored vulnerabilities. 1 public exploit is recorded.

Timeline

1. 30-03-2026
   PublishedVulnerability first disclosed.
2. 30-03-2026
   Last modifiedVulnerability information updated.

Description

A weakness has been identified in Totolink A3300R 17.0.0cu.557_b20221024. This issue affects the function setUPnPCfg of the file /cgi-bin/cstecgi.cgi. This manipulation of the argument enable causes command injection. The attack is possible to be carried out remotely. The exploit has been made available to the public and could be used for attacks.

• CWE-74Improper Neutralization of Special Elements in Output Used by a Downstream Component ('Injection')The product constructs all or part of a command, data structure, or record using externally-influenced input from an upstream component, but it does not neutralize or incorrectly neutralizes special elements that could modify how it is parsed or interpreted when it is sent to a downstream component.
• 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.