D-Link DPH-400S/SE VoIP Phone Hardcoded Password Vulnerability

A vulnerability exists in the D-Link DPH-400S and DPH-400SE VoIP phones running firmware version 1.01, due to hardcoded provisioning variables that include sensitive user credentials. An attacker with access to the firmware image can extract these credentials using static analysis tools, potentially leading to unauthorized access to device functions or user accounts. This issue arises from the insecure storage of sensitive information in the firmware binary.

Impact

Exploitation of this vulnerability allows for the recovery of valid provisioning or administrative credentials, leading to unauthorized access to VoIP systems or services and the potential interception or manipulation of SIP-based communication sessions.

Reproduction

The vulnerability can be reproduced by performing a static analysis of the DPH-400S_DPH-400SE_A1_FW_v1.01.bin firmware image. The hardcoded strings for the user and admin passwords can be extracted using the 'strings' command, confirming their presence in the firmware binary without any encryption or access control.

Remediation

D-Link has confirmed that the DPH-400S and DPH-400SE models have reached End-of-Life and will not receive updates. Users are advised to retire or replace these devices, restrict access to firmware files and provisioning logs, isolate legacy VoIP equipment from internet-facing networks, and avoid reusing provisioning credentials across systems.