CVE-2025-11098: D-Link DIR-823X RCE Vulnerability

CVE-2025-11098 Overview

CVE-2025-11098 is a command injection vulnerability affecting the D-Link DIR-823X router running firmware version 250416. The flaw resides in the /goform/set_wifi_blacklists endpoint, where the macList parameter is passed to a system shell without proper sanitization. A remote attacker with low-privileged access can inject operating system commands through this parameter. The exploit details have been published, lowering the barrier for opportunistic exploitation. The vulnerability is categorized under [CWE-74] for improper neutralization of special elements in output used by a downstream component.

Critical Impact
Authenticated remote attackers can execute arbitrary commands on the underlying router operating system, leading to device compromise and lateral movement into protected networks.

Affected Products

D-Link DIR-823X router (hardware)
D-Link DIR-823X firmware version 250416
Devices exposing the /goform/set_wifi_blacklists administrative endpoint

Discovery Timeline

2025-09-28 - CVE-2025-11098 published to the National Vulnerability Database (NVD)
2026-06-17 - Last updated in NVD database

Technical Details for CVE-2025-11098

Vulnerability Analysis

The D-Link DIR-823X web management interface exposes the /goform/set_wifi_blacklists handler for configuring Wi-Fi MAC address blacklists. The handler accepts a macList parameter that is concatenated into a shell command without input validation or escaping. Attackers can append shell metacharacters such as ;, &&, or backticks to break out of the intended command context. The injected payload runs with the privileges of the web server process, which on consumer routers is typically root.

The exploit is performed over the network against the router's management interface. According to the assigned metrics, the attacker must hold low-level privileges, which on many D-Link consumer devices corresponds to default or user-assigned credentials. The EPSS score of 4.125% places this issue in the 89th percentile for likelihood of exploitation activity.

Root Cause

The root cause is the absence of input sanitization on the macList argument before it reaches a system call. The handler treats user-supplied data as trusted command components rather than validated MAC address strings. A regular expression filter restricting input to hexadecimal MAC format would block the attack class.

Attack Vector

The attack is performed remotely over HTTP or HTTPS against the router's web interface. An authenticated session is required, but session reuse, cross-site request forgery, or default credentials can supply the required access. The attacker submits a crafted POST request to /goform/set_wifi_blacklists with a macList value containing shell metacharacters followed by arbitrary commands. The router executes the injected commands and returns the response to the management interface. Public exploit documentation describing the parameter manipulation is available in the referenced GitHub WiFi Blacklist Guide.

No verified exploit code is reproduced here. Refer to the VulDB CTI #326179 record for technical artifacts.

Detection Methods for CVE-2025-11098

Indicators of Compromise

HTTP POST requests to /goform/set_wifi_blacklists containing shell metacharacters (;, |, &, backticks, $()) inside the macList parameter
Unexpected outbound connections from the router to attacker-controlled infrastructure shortly after configuration changes
New or modified accounts, cron entries, or iptables rules on the device that were not introduced by an administrator
Persistent processes on the router binding to non-standard ports

Detection Strategies

Inspect web server access logs on the router for requests targeting /goform/set_wifi_blacklists with macList values that do not match the regex ^([0-9A-Fa-f]{2}:){5}[0-9A-Fa-f]{2}$
Deploy network intrusion detection signatures that flag POST bodies containing shell metacharacters bound for D-Link goform endpoints
Correlate management-plane HTTP activity with subsequent outbound DNS or TCP connections from the router's WAN interface

Monitoring Recommendations

Capture NetFlow or packet metadata for traffic to and from the router management interface and alert on anomalies
Forward router syslog data to a centralized log platform and baseline normal administrative activity
Track firmware versions across deployed D-Link devices and flag any unit still running version 250416

How to Mitigate CVE-2025-11098

Immediate Actions Required

Restrict access to the router's web management interface to trusted internal management VLANs or specific source IP addresses
Disable remote WAN-side administration if it is enabled on the affected device
Rotate administrative credentials and remove any default or shared accounts
Audit recent configuration changes and log entries for evidence of exploitation

Patch Information

No vendor advisory or fixed firmware version was listed in the NVD record at the time of publication. Consult the D-Link Official Website support pages for the DIR-823X for any subsequent firmware release that addresses CVE-2025-11098. Until a patched firmware is available, treat the device as exposed and apply compensating controls.

Workarounds

Place the affected device behind a network segment that blocks untrusted hosts from reaching TCP/80 and TCP/443 on the router
Enforce strong administrator passwords and disable any unused management protocols
Replace the device with a supported model if the vendor does not issue a fix within an acceptable timeframe

bash

# Example: restrict router management interface to a trusted host on an upstream firewall
iptables -A FORWARD -p tcp -d 192.0.2.1 --dport 443 -s 10.10.10.50 -j ACCEPT
iptables -A FORWARD -p tcp -d 192.0.2.1 --dport 443 -j DROP
iptables -A FORWARD -p tcp -d 192.0.2.1 --dport 80  -j DROP