CVE-2024-47924 Overview
CVE-2024-47924 is a cross-site scripting (XSS) vulnerability in the Boa web server, classified under [CWE-79]: Improper Neutralization of Input During Web Page Generation. The flaw allows remote attackers to inject malicious script content into web pages generated by the server. Exploitation requires no authentication and no user interaction over the network. Boa is a lightweight HTTP server frequently embedded in IoT devices, routers, and other resource-constrained systems, which broadens the potential attack surface.
Critical Impact
Unauthenticated remote attackers can inject arbitrary script content into responses served by Boa, enabling session theft, credential harvesting, and unauthorized actions in the context of authenticated administrators.
Affected Products
- Boa web server (vendor and version details not enumerated in the NVD record)
- Embedded systems and IoT devices that bundle the Boa HTTP server
- Network appliances and routers that ship Boa as their administrative web interface
Discovery Timeline
- 2024-12-30 - CVE-2024-47924 published to NVD
- 2026-06-17 - Last updated in NVD database
Technical Details for CVE-2024-47924
Vulnerability Analysis
The vulnerability stems from improper neutralization of user-supplied input that is reflected into HTTP responses generated by the Boa web server. When the server constructs HTML output using request parameters, URI segments, or header values, it fails to apply context-appropriate output encoding. An attacker can craft a request containing script payloads that the server returns unmodified in the response body.
When a victim browser renders the response, the injected script executes in the security context of the Boa-hosted origin. Because Boa typically serves administrative panels for embedded devices, the executing script inherits any active administrator session. This enables actions such as configuration changes, credential theft, and pivoting deeper into the internal network.
The attack vector is network-based with low complexity. No privileges or user interaction beyond visiting a malicious link are required to deliver the payload to a targeted administrator.
Root Cause
The root cause is the absence of HTML entity encoding and context-aware sanitization in code paths that emit user-controlled values into the response. Reflected request data flows into the response generator without being escaped for the HTML, attribute, or JavaScript contexts in which it ultimately appears.
Attack Vector
An attacker delivers a crafted URL to a target administrator through phishing, a malicious link, or a watering-hole page. When the administrator clicks the link while authenticated to the Boa-hosted interface, the embedded payload executes in their browser. The attacker can then exfiltrate session cookies, issue authenticated requests on the user's behalf, or modify rendered content to capture credentials.
For implementation specifics and proof-of-concept details, refer to the Israeli Government CVE Advisories listed in the NVD record. No verified public exploit code is available at this time.
Detection Methods for CVE-2024-47924
Indicators of Compromise
- HTTP request logs containing reflected query parameters, URI segments, or header values with <script>, javascript:, onerror=, or onload= patterns.
- Outbound browser connections from administrator workstations to unfamiliar domains shortly after access to a Boa-hosted interface.
- Unexpected configuration changes on embedded devices that coincide with administrator browser activity.
Detection Strategies
- Inspect HTTP traffic to and from devices running Boa for request parameters carrying HTML or JavaScript markup.
- Deploy web application firewall rules that flag reflected XSS patterns targeting common Boa endpoints.
- Correlate administrator authentication events with subsequent anomalous configuration writes on embedded devices.
Monitoring Recommendations
- Enable verbose access logging on Boa instances and forward logs to a centralized analytics platform for pattern matching.
- Monitor browsers used by network administrators for execution of scripts originating from internal management URLs.
- Track firmware inventories to identify all devices that embed the Boa HTTP server and require monitoring coverage.
How to Mitigate CVE-2024-47924
Immediate Actions Required
- Restrict access to Boa-hosted administrative interfaces to dedicated management networks or VPNs.
- Disable remote administration over WAN interfaces on devices that expose Boa to untrusted networks.
- Instruct administrators to authenticate to embedded device interfaces only from isolated browser sessions.
Patch Information
The Boa web server has been unmaintained since 2005, so upstream patches are unlikely. Device vendors that ship Boa must issue firmware updates that either remove the vulnerable code path or replace Boa with a maintained HTTP server. Consult the Israeli Government CVE Advisories and the firmware vendor's support channels for product-specific guidance.
Workarounds
- Place Boa-hosted devices behind a reverse proxy that performs HTML output encoding and rejects requests containing script payloads.
- Apply web application firewall signatures that block reflected XSS attempts on the administrative URL paths.
- Enforce strict Content Security Policy headers via an upstream proxy to limit script execution in administrator browsers.
- Where feasible, replace devices running the end-of-life Boa server with hardware that uses a maintained web stack.
Disclaimer: This content was generated using AI. While we strive for accuracy, please verify critical information with official sources.
