Overview
A critical command injection vulnerability, identified as CVE-2025-60701, has been discovered in the D-Link DIR-882 Router firmware version DIR882A1_FW102B02. This flaw allows an unauthenticated remote attacker to execute arbitrary commands on the affected device. This poses a significant security risk, potentially leading to complete compromise of the router and the network it serves.
Technical Details
The vulnerability resides in the prog.cgi and rc binaries of the firmware. Specifically, the issue stems from the way email configuration parameters are handled:
- The
sub_433188function withinprog.cgitakes user-supplied email configuration parameters (EmailFrom,EmailTo,SMTPServerAddress,SMTPServerPort,AccountName) from HTTP requests. - These parameters are then stored in NVRAM using the
nvram_safe_setfunction. - Later, the
sub_448FDCfunction in thercbinary retrieves these NVRAM values usingnvram_safe_get. - Critically, the retrieved values are concatenated into shell commands that are then executed using the
twsystem()function without proper sanitization.
This lack of sanitization allows an attacker to inject malicious shell commands within the email configuration parameters. Because the attacker is unauthenticated, they can directly send malicious HTTP requests to trigger the vulnerability.
Proof-of-concept exploits demonstrating this vulnerability are publicly available. These exploits typically involve crafting HTTP requests with specially crafted payloads in the email configuration parameters.
Example Vulnerable Code Flow (Simplified):
// In prog.cgi (simplified)
EmailFrom = request.getParameter("EmailFrom");
nvram_safe_set("email_from", EmailFrom);
// In rc (simplified)
EmailFrom = nvram_safe_get("email_from");
command = "sendmail -f " + EmailFrom + " recipient@example.com";
twsystem(command); // Command executed without sanitization!
CVSS Analysis
Currently, the CVSS score and severity are not yet assigned for CVE-2025-60701. However, given the nature of the vulnerability (unauthenticated remote command execution), it is highly likely that it will receive a Critical severity rating and a CVSS score in the range of 9.0-10.0.
Possible Impact
Successful exploitation of CVE-2025-60701 can have severe consequences:
- Complete Router Compromise: An attacker can gain full control of the router.
- Malware Installation: The attacker can install malware on the router, potentially turning it into a botnet node.
- Data Theft: Sensitive information stored on the network or passing through the router could be stolen.
- Network Manipulation: The attacker could modify DNS settings, redirect traffic, or launch attacks against other devices on the network.
- Service Disruption: The router could be rendered unusable, disrupting network connectivity.
Mitigation and Patch Steps
The most important step is to update your D-Link DIR-882 router to the latest firmware version as soon as it becomes available. Check the D-Link Security Bulletin page for updates and announcements.
In the interim, consider the following temporary mitigations (though these are not foolproof and should not be considered a replacement for patching):
- Disable Remote Management: If possible, disable remote access to the router’s web interface.
- Restrict Access: If remote management is necessary, restrict access to a specific IP address range.
- Monitor Network Traffic: Monitor network traffic for suspicious activity originating from the router.
- Firewall Configuration: Ensure your firewall is properly configured to block unauthorized access to your network.
D-Link has also indicated they may be releasing new security bulletin for impacted devices. Check the D-Link Security Bulletin page for updates and announcements.
