CVE-2026-3841: 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…

PriorityP267high8.8CVSS 3.1

AVNACLPRLUINSUCHIHAH

EPSS

1.77%

75.4th percentile

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.

Affected

2 ranges

Vendor	Product	Version range	Fixed in
tp-link	tl-mr6400_firmware	< 1.9.0	1.9.0
tp-link_systems_inc	tl-mr6400_v5.3	< 1.9.0 Build 260108	1.9.0 Build 260108

CVSS provenance

nvdv3.18.8HIGHCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

nvdv4.08.5HIGHCVSS:4.0/AV:A/AC:L/AT:N/PR:H/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X

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