CVE-2025-62673: TP-Link Archer AX53 Buffer Overflow Flaw

CVE-2025-62673 Overview

A heap-based buffer overflow vulnerability exists in the TP-Link Archer AX53 v1.0 router, specifically within the tdpserver modules. This vulnerability allows adjacent network attackers to cause a segmentation fault or potentially execute arbitrary code by sending a specially crafted network packet containing a maliciously formed field to the affected device.

Critical Impact

Adjacent network attackers with low privileges can exploit this heap overflow to crash the router or achieve arbitrary code execution, potentially compromising the entire network segment.

Affected Products

• TP-Link Archer AX53 v1.0 through firmware version 1.3.1 Build 20241120
• TP-Link Archer AX53 v1.0 tdpserver modules

Discovery Timeline

• 2026-02-03 - CVE-2025-62673 published to NVD
• 2026-02-04 - Last updated in NVD database

Technical Details for CVE-2025-62673

Vulnerability Analysis

This vulnerability is classified as CWE-122 (Heap-based Buffer Overflow), which occurs when a program writes data beyond the allocated boundary of a heap buffer. In the context of the TP-Link Archer AX53 router, the tdpserver module fails to properly validate the length or contents of certain fields within incoming network packets. When an attacker sends a specially crafted packet with a maliciously formed field, the vulnerable code writes data past the allocated heap buffer boundary.

The exploitation requires the attacker to be on an adjacent network segment (such as the same LAN or Wi-Fi network) and possess low-level privileges. No user interaction is required for successful exploitation. The potential consequences include denial of service through a segmentation fault crash or, more critically, arbitrary code execution with the privileges of the tdpserver process running on the router.

Root Cause

The root cause of this vulnerability lies in insufficient bounds checking within the tdpserver module's packet parsing functionality. When processing incoming network packets, the module allocates a fixed-size buffer on the heap but does not properly validate that incoming data fits within the allocated space. This allows an attacker to supply oversized or malformed field data that overflows the heap buffer, corrupting adjacent memory structures.

Attack Vector

The attack is conducted from an adjacent network position, meaning the attacker must have access to the same network segment as the vulnerable router. The attacker crafts a malicious network packet targeting the tdpserver service with a specially formed field designed to trigger the heap overflow condition. Upon processing this packet, the router's tdpserver module writes beyond the allocated heap buffer, potentially overwriting heap metadata, function pointers, or other critical data structures.

The vulnerability manifests in the tdpserver module's packet processing logic. When a network packet arrives with a malformed field that exceeds expected bounds, the module copies this data into a heap-allocated buffer without proper length validation. This allows heap corruption that can be leveraged for denial of service or code execution. For detailed technical analysis, refer to the Talos Intelligence Vulnerability Reports.

Detection Methods for CVE-2025-62673

Indicators of Compromise

• Unexpected crashes or reboots of TP-Link Archer AX53 routers
• Segmentation fault errors in router logs related to tdpserver
• Anomalous network traffic patterns targeting the tdpserver service port
• Unusual memory consumption or behavior on the affected router

Detection Strategies

• Monitor network traffic for malformed packets directed at TP-Link router services on the local network
• Implement network intrusion detection rules to identify oversized or malformed tdpserver protocol packets
• Deploy network segmentation to limit adjacent network access to router management interfaces
• Review router logs for crash dumps or unexpected service restarts of tdpserver

Monitoring Recommendations

• Enable verbose logging on TP-Link routers where available to capture service crashes
• Implement network monitoring at the LAN level to detect unusual traffic patterns targeting router services
• Set up alerts for router availability issues that may indicate exploitation attempts
• Regularly audit devices connected to the same network segment as vulnerable routers

How to Mitigate CVE-2025-62673

Immediate Actions Required

• Update TP-Link Archer AX53 v1.0 firmware to the latest available version from TP-Link
• Restrict network access to the router's management interfaces to trusted devices only
• Implement network segmentation to isolate IoT and network infrastructure devices
• Monitor the router for signs of exploitation or unusual behavior

Patch Information

TP-Link has provided firmware updates to address this vulnerability. Users should download and install the latest firmware version from the official TP-Link Archer AX53 Firmware Download page. Firmware version 1.3.1 Build 20241120 and earlier are affected, so ensure the installed firmware is newer than this build. Additional support information is available at the TP-Link FAQ on Device Issues.

Workarounds

• Disable remote management features if not required to reduce attack surface
• Implement MAC address filtering to restrict which devices can communicate with the router
• Use VLAN segmentation to isolate the router from untrusted devices on the network
• Consider deploying a network firewall or IDS to monitor and filter traffic to vulnerable services

# Firmware update verification steps
# 1. Download latest firmware from TP-Link official website
# 2. Access router admin panel at http://192.168.0.1 (default)
# 3. Navigate to Advanced > System Tools > Firmware Upgrade
# 4. Select downloaded firmware file and click Upgrade
# 5. Wait for router to reboot and verify new firmware version