CVE-2025-62501: TP-Link Archer AX53 Info Disclosure Flaw

CVE-2025-62501 Overview

CVE-2025-62501 is an SSH Hostkey misconfiguration vulnerability affecting TP-Link Archer AX53 v1.0 routers, specifically within the tmpserver modules. This vulnerability allows attackers on an adjacent network to intercept device credentials through a specially crafted man-in-the-middle (MITM) attack. The improper SSH host key configuration enables credential theft, potentially leading to unauthorized device access if the captured credentials are reused elsewhere.

Critical Impact

Attackers on the local network segment can intercept SSH communications and harvest device credentials, enabling unauthorized router access and potential network compromise.

Affected Products

• TP-Link Archer AX53 v1.0 firmware through 1.3.1 Build 20241120
• TP-Link Archer AX53 v1.0 with tmpserver modules enabled

Discovery Timeline

• 2026-02-03 - CVE CVE-2025-62501 published to NVD
• 2026-02-04 - Last updated in NVD database

Technical Details for CVE-2025-62501

Vulnerability Analysis

This vulnerability stems from improper SSH host key management within the TP-Link Archer AX53 router firmware. The weakness is classified under CWE-322 (Key Exchange without Entity Authentication), which indicates that the SSH implementation fails to properly authenticate the server's identity during the key exchange process.

The tmpserver module responsible for SSH functionality does not adequately validate or generate unique host keys, creating an opportunity for attackers to impersonate the device. When a client connects to what it believes is the legitimate router, an attacker positioned on the same network segment can intercept and relay communications, capturing authentication credentials in the process.

The adjacent network attack vector requirement means the attacker must be on the same local network segment as the target device, which is common in home and small office environments where the Archer AX53 is typically deployed. While this limits remote exploitation, it significantly increases risk in shared network environments.

Root Cause

The root cause of CVE-2025-62501 is improper key management in the SSH implementation within the tmpserver modules. The vulnerability arises from the device's failure to properly establish cryptographic trust during SSH key exchange operations. This may involve the use of predictable, static, or improperly validated host keys that allow an attacker to successfully perform entity impersonation during the key exchange handshake.

Attack Vector

The attack requires the adversary to be positioned on an adjacent network, typically the same LAN segment as the target router. The attacker performs a man-in-the-middle attack by:

1. Intercepting SSH connection attempts between a legitimate client and the Archer AX53 router
2. Presenting a forged SSH host key to the connecting client
3. Relaying communications between the client and router while capturing credentials
4. Using harvested credentials for unauthorized access to the device or other systems where credentials may be reused

The attack exploits the fact that the SSH implementation does not properly enforce entity authentication during key exchange, allowing the attacker to insert themselves into the communication channel without detection.

Detection Methods for CVE-2025-62501

Indicators of Compromise

• Unexpected SSH host key changes or warnings when connecting to the router
• Presence of unknown devices on the local network performing ARP spoofing
• Multiple failed SSH authentication attempts followed by successful logins from different IP addresses
• Network traffic anomalies indicating potential MITM activity between clients and the router

Detection Strategies

• Monitor for ARP spoofing attacks on the local network segment using network intrusion detection systems
• Implement SSH host key verification and alert on host key mismatches or changes
• Deploy network monitoring to detect suspicious traffic patterns between clients and the router's SSH service
• Review SSH connection logs for authentication attempts from unexpected source addresses

Monitoring Recommendations

• Enable logging on the Archer AX53 router and forward logs to a centralized SIEM for analysis
• Monitor network traffic for signs of MITM attacks including ARP poisoning and DNS spoofing
• Implement client-side SSH key pinning where possible to detect host key anomalies
• Conduct regular network scans to identify rogue devices that may be performing interception attacks

How to Mitigate CVE-2025-62501

Immediate Actions Required

• Update the TP-Link Archer AX53 v1.0 firmware to the latest available version from the TP-Link Archer AX53 Firmware Download page
• Disable SSH access on the router if not actively required for administration
• Limit network access to the router's management interfaces to trusted devices only
• Avoid credential reuse across different systems and services
• Implement network segmentation to isolate administrative access from general network traffic

Patch Information

TP-Link has acknowledged this vulnerability. Users should check for firmware updates addressing this issue through the official TP-Link support channels. The affected firmware versions include builds through 1.3.1 Build 20241120. Additional technical details may be available through Talos Intelligence Vulnerability Reports.

Workarounds

• Disable SSH service on the router and use alternative management methods such as HTTPS web interface
• Implement network-level access controls to restrict who can communicate with the router's SSH service
• Use a separate, isolated management network for router administration
• Deploy host-based firewalls on client systems to prevent unauthorized network redirections
• Enable static ARP entries on critical devices to mitigate ARP spoofing attacks that facilitate MITM

# Example: Disable SSH access via router CLI (if available)
# Access router administration interface
# Navigate to: Advanced > System Tools > Administration
# Locate SSH/Remote Management settings
# Disable SSH access or restrict to specific IP addresses