CVE-2024-21773: Critical Command Injection Vulnerability in TP-Link Routers

Overview

In January 2024, a severe vulnerability tracked as CVE-2024-21773 was disclosed, affecting multiple TP-Link routers and Deco devices. This flaw enables unauthenticated attackers on the local network to execute arbitrary operating system commands without prior credentials.

With a CVSS v3.1 score of 8.8 (High), this vulnerability poses a significant risk to home and small office networks, especially those relying on TP-Link’s parental control features.

Vulnerability Summary

• CVE ID: CVE-2024-21773

• Severity: High (CVSS 8.8)

• Attack Vector: Local network (LAN or Wi-Fi)

• Attack Complexity: Low

• Authentication Required: None

• Impact: Remote command execution as root on the device

Affected Products

The vulnerability affects the following TP-Link devices prior to the firmware versions listed below:

Reference: JVN Vulnerability Advisory (Japan)

How the Exploit Works (Conceptual)

Although a full proof-of-concept has not been publicly disclosed, the vulnerability is believed to exist in the parental control configuration interface. Attackers connected to the same network can submit specially crafted HTTP requests that inject system-level commands through vulnerable parameters.

Conceptual Attack Example (Not Actual Code):

Such payloads could allow attackers to force reboots, manipulate settings, or execute arbitrary commands as root.

Potential Risks

If successfully exploited, attackers could:

• Redirect DNS traffic to malicious sites

• Eavesdrop on network communications

• Install persistent malware or backdoors

• Disable firewalls or parental controls

• Launch attacks against internal or external systems

Although this is a local exploit, attackers could compromise a nearby device first (like a phone or smart TV) to gain entry to the network and escalate their attack from there.

Mitigation Recommendations

1. Update Firmware

TP-Link has released patches. Upgrade to the following firmware builds or newer:

• AX3000: Build 20231115 or later

• AX5400: Build 20231115 or later

• Deco X50: Build 20231122 or later

• Deco XE200: Build 20231120 or later

Visit the TP-Link support site to download updates.

2. Disable Parental Controls (if unpatched)

As a temporary mitigation, disable the parental control features, which are linked to the vulnerable functionality.

3. Secure Local Network Access

• Use strong Wi-Fi passwords

• Disable WPS functionality

• Limit device admin access to trusted machines only

• Segment IoT devices on a guest network if possible

4. Monitor for Suspicious Behavior

Review logs (if available) for unknown administrative actions, unauthorized reboots, or rule changes.

Conclusion

CVE-2024-21773 highlights the growing importance of secure firmware in home and SOHO routers. Router vulnerabilities offer a high return for attackers, making them a prime target for local and lateral movement.

For anyone using TP-Link devices, prompt firmware updates and network hardening are essential steps in defending against this class of vulnerability.

We will continue to monitor this CVE and provide updates if technical proof-of-concepts or exploit scripts are released publicly.