CVE-2026-4205: D-Link DNS-1550-04 app_mgr.cgi FTP_Server_BlockIP_Del command injection

Published Mar 16, 2026
·
Updated

A vulnerability has been found in D-Link DNS-120, DNR-202L, DNS-315L, DNS-320, DNS-320L, DNS-320LW, DNS-321, DNR-322L, DNS-323, DNS-325, DNS-326, DNS-327L, DNR-326, DNS-340L, DNS-343, DNS-345, DNS-726-4, DNS-1100-4, DNS-1200-05 and DNS-1550-04 up to 20260205. The impacted element is the function cgirefreshdb/FTPServerBlockIPAdd/FTPServerBlockIPDel of the file /cgi-bin/appmgr.cgi. Such manipulation leads to command injection. The attack can be executed remotely. The exploit has been disclosed to the public and may be used.

Affected Software

60 affected components
D-Link DNS-120<=20260205
D-Link DNR-202L<=20260205
D-Link DNS-315L<=20260205
D-Link DNS-320<=20260205
D-Link DNS-320L<=20260205
D-Link DNS-320LW<=20260205
D-Link DNS-321<=20260205
D-Link DNR-322L<=20260205
D-Link DNS-323<=20260205
D-Link DNS-325<=20260205
D-Link DNS-326<=20260205
D-Link DNS-327L<=20260205
D-Link DNR-326<=20260205
D-Link DNS-340L<=20260205
D-Link DNS-343<=20260205
D-Link DNS-345<=20260205
D-Link DNS-726-4<=20260205
D-Link DNS-1100-4<=20260205
D-Link DNS-1200-05<=20260205
D-Link DNS-1550-04<=20260205
All of the following
Dlink Dnr-202l Firmware<=2026-02-05
Dlink Dnr-202l
All of the following
Dlink Dnr-326 Firmware<=2026-02-05
Dlink Dnr-326
All of the following
Dlink Dns-1100-4 Firmware<=2026-02-05
Dlink Dns-1100-4
All of the following
Dlink Dns-120 Firmware<=2026-02-05
Dlink Dns-120
All of the following
Dlink Dns-1200-05 Firmware<=2026-02-05
Dlink Dns-1200-05
All of the following
Dlink Dns-1550-04 Firmware<=2026-02-05
Dlink Dns-1550-04
All of the following
Dlink Dns-315l Firmware<=2026-02-05
Dlink Dns-315l
All of the following
Dlink Dns-320 Firmware<=2026-02-05
Dlink Dns-320
All of the following
Dlink Dns-320l Firmware<=2026-02-05
Dlink Dns-320l
All of the following
Dlink Dns-320lw Firmware<=2026-02-05
Dlink Dns-320lw
All of the following
Dlink Dns-321 Firmware<=2026-02-05
Dlink Dns-321
All of the following
Dlink Dns-322l Firmware<=2026-02-05
Dlink Dns-322l
All of the following
Dlink Dns-323 Firmware<=2026-02-05
Dlink Dns-323
All of the following
Dlink Dns-325 Firmware<=2026-02-05
Dlink Dns-325
All of the following
Dlink Dns-326 Firmware<=2026-02-05
Dlink Dns-326
All of the following
Dlink Dns-327l Firmware<=2026-02-05
Dlink Dns-327l
All of the following
Dlink Dns-340l Firmware<=2026-02-05
Dlink Dns-340l
All of the following
Dlink Dns-343 Firmware<=2026-02-05
Dlink Dns-343
All of the following
Dlink Dns-345 Firmware<=2026-02-05
Dlink Dns-345
All of the following
Dlink Dns-726-4 Firmware<=2026-02-05
Dlink Dns-726-4

Event History

Mar 16, 2026
CVE Published
via MITRE·01:32 AM
Data Sourced
via MITRE·01:32 AM
DescriptionSeverityWeakness
Data Sourced
via NVD·02:20 PM
DescriptionSeverityWeaknessAffected Software
Oct 9, 58191
Event
via FIRST·06:15 AM
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Frequently Asked Questions

1

What is the severity of CVE-2026-4205?

CVE-2026-4205 is classified as a high severity vulnerability due to its potential for remote code execution.

2

How do I fix CVE-2026-4205?

To fix CVE-2026-4205, users should update their affected D-Link devices to the latest firmware version available.

3

Which D-Link products are affected by CVE-2026-4205?

Affected D-Link products include the DNS-120, DNS-315L, DNS-320, DNS-323, DNS-340L, and several other models.

4

What type of attack can CVE-2026-4205 facilitate?

CVE-2026-4205 allows attackers to inject commands into the FTP server, potentially leading to unauthorized access.

5

Is there a workaround for CVE-2026-4205 if I cannot update immediately?

A temporary workaround is to disable the FTP server feature on the affected D-Link devices until a firmware update can be applied.

Contact

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