Source: cve@mitre.org
Cross-site scripting (XSS) vulnerability on the HOT HOTBOX router with software 2.1.11 allows remote attackers to inject arbitrary web script or HTML via a crafted DHCP Host Name option, which is not properly handled during rendering of the DHCP table in wlanAccess.asp.
HOT HOTBOX routers running software version 2.1.11 are vulnerable to a cross-site scripting (XSS) attack. Attackers can inject malicious scripts into the router's web interface by crafting a malicious DHCP Host Name option, potentially allowing them to steal user credentials, redirect users to malicious websites, or gain control of the router's web interface.
Step 1: Payload Delivery: The attacker crafts a malicious DHCP Host Name. This involves setting the Host Name option in a DHCP request to a string containing malicious JavaScript code (e.g., <script>alert('XSS')</script>).
Step 2: DHCP Request: The attacker's device sends a DHCP request to the HOT HOTBOX router.
Step 3: DHCP Response: The router receives the DHCP request and assigns an IP address to the attacker's device, along with the attacker-controlled Host Name.
Step 4: Data Storage: The router stores the malicious Host Name in its DHCP configuration data.
Step 5: Web Page Rendering: When an administrator accesses the wlanAccess.asp page, the router retrieves the DHCP configuration data, including the malicious Host Name.
Step 6: XSS Execution: The wlanAccess.asp page renders the DHCP table, directly incorporating the attacker-controlled Host Name into the HTML without proper sanitization. This causes the malicious JavaScript code to execute in the administrator's browser, enabling the XSS attack.
The vulnerability stems from a failure to properly sanitize user-supplied input within the DHCP Host Name field before rendering it in the wlanAccess.asp page. Specifically, the router's web application directly incorporates the DHCP Host Name value into the HTML output without any encoding or filtering of special characters. This allows an attacker to inject arbitrary HTML and JavaScript code. The root cause is a lack of input validation and output encoding on the server-side, leading to a stored XSS vulnerability. The wlanAccess.asp page likely uses a function to retrieve the DHCP Host Name from the DHCP configuration, and this function does not sanitize the input before displaying it in the DHCP table.
While no specific APT groups are directly linked to this vulnerability, it is a low-hanging fruit that could be exploited by various threat actors. The ease of exploitation makes it attractive for opportunistic attacks. CISA KEV status: Not listed.
Network traffic analysis: Monitor DHCP traffic for unusual Host Name values, especially those containing HTML or JavaScript code.
Web server logs: Examine the web server logs for requests to wlanAccess.asp and look for unusual patterns or suspicious user agents.
Forensic analysis: Examine the router's configuration files for the presence of malicious Host Name values.
IDS/IPS signatures: Implement signatures to detect malicious DHCP Host Name payloads.
Monitor for unusual HTTP requests originating from the router's IP address, especially those containing JavaScript or HTML.
Upgrade to a patched version of the HOT HOTBOX router firmware. If no patch is available, consider replacing the router.
Implement input validation: Ensure that all user-supplied input, including the DHCP Host Name, is properly validated and sanitized before being used.
Implement output encoding: Encode all output to prevent XSS attacks. Specifically, HTML encode the DHCP Host Name before rendering it in the wlanAccess.asp page.
Disable DHCP Host Name configuration if not needed.
Implement a Web Application Firewall (WAF) to filter malicious requests.