CVE-2026-3841: tp-link systems inc. tl-mr6400 v5.3 OS Command Injection

Vulnerability summary

CVE-2026-3841 is a high (CVSS 8.8) OS Command Injection vulnerability in tp-link systems inc. tl-mr6400 v5.3. EPSS estimates a 2.88% chance of exploitation in the next 30 days, higher than 86.7% of scored vulnerabilities.

Timeline

1. 12-03-2026
   PublishedVulnerability first disclosed.
2. 13-03-2026
   Last modifiedVulnerability information updated.

Description

A command injection vulnerability has been identified in the Telnet command-line interface (CLI) of TP-Link TL-MR6400 v5.3. This issue is caused by insufficient sanitization of data processed during specific CLI operations. An authenticated attacker with elevated privileges may be able to execute arbitrary system commands. Successful exploitation may lead to full device compromise, including potential loss of confidentiality, integrity, and availability.

• 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.