1. Introduction
WebCam Watchdog sresult.exe is vulnerable to a cross-site scripting (XSS) attack. This means an attacker could inject malicious scripts into the web server, potentially stealing cookie-based credentials from legitimate users of the site. Affected systems are typically those running WebCamSoft’s watchdog software with a CGI application enabled. A successful exploit poses a medium risk to confidentiality through credential theft.
2. Technical Explanation
- Root cause: Missing input validation on the ‘cam’ parameter within the sresult.exe CGI script.
- Exploit mechanism: An attacker crafts a URL containing malicious JavaScript code in the ‘cam’ parameter, which is then reflected back to the user’s browser and executed. For example:
http://example.com/cgi-bin/sresult.exe?cam= - Scope: WebCamSoft watchdog software running a CGI application; specifically, versions prior to any known patch release.
3. Detection and Assessment
Confirming vulnerability requires checking for the presence of the vulnerable script and testing its input handling. A thorough assessment involves attempting to inject test XSS payloads.
- Quick checks: Verify WebCamSoft watchdog software is installed on the system. Check if the CGI application is enabled by looking for ‘sresult.exe’ in the web server’s configuration directory (e.g., /cgi-bin/).
- Scanning: Nessus plugin ID 30986 may identify this vulnerability, but results should be verified manually.
- Logs and evidence: Examine web server logs for requests to ‘sresult.exe’ containing suspicious characters or JavaScript code in the ‘cam’ parameter. Look for reflected output containing injected payloads.
# Example command placeholder:
# No specific command available, check webserver config files.
4. Solution / Remediation Steps
Currently, there is no known solution at this time. The following steps outline a temporary mitigation strategy and preparation for future patching.
4.1 Preparation
- Ensure you have access to restore the original configuration if needed. A roll back plan involves restoring the backed-up configuration files and restarting the web server.
- A change window may be required depending on your organisation’s policies; approval from a security lead is recommended.
4.2 Implementation
- Step 1: Disable the CGI application if it is not essential for functionality. This can usually be done through the web server configuration file (e.g., Apache httpd.conf or IIS Manager).
- Step 2: Monitor security tracker and vendor websites for patch releases addressing this vulnerability.
- Step 3: Once a patch becomes available, download and install it according to the vendor’s instructions.
4.3 Config or Code Example
Before
# Example Apache configuration - CGI enabled
ScriptAlias /cgi-bin "/var/www/cgi-bin"
Options +ExecCGI
After
# Example Apache configuration - CGI disabled
# ScriptAlias /cgi-bin "/var/www/cgi-bin"
# Options +ExecCGI
4.4 Security Practices Relevant to This Vulnerability
Several security practices can help prevent this type of issue. Input validation is key, as is the principle of least privilege.
- Practice 1: Least privilege – restrict access to sensitive resources like CGI scripts to only those users who absolutely need it.
4.5 Automation (Optional)
No automation is recommended at this time due to the lack of a known patch.
# No script available, as there is no fix yet.
5. Verification / Validation
Confirming the fix involves verifying that the CGI application is disabled or that injected payloads are no longer reflected in the output. A smoke test ensures basic web server functionality remains intact.
- Post-fix check: Verify that requests to ‘sresult.exe’ return a 404 error (if disabled) or do not reflect injected JavaScript code.
- Re-test: Attempt the earlier exploitation steps with the same payload; it should no longer be possible to inject and execute malicious scripts.
- Smoke test: Confirm that other web server functionality, such as serving static content, continues to work as expected.
- Monitoring: Monitor web server logs for any attempts to access ‘sresult.exe’ or similar CGI scripts; investigate any unusual activity.
# Example command and expected output (after disabling CGI)
curl http://example.com/cgi-bin/sresult.exe
404 Not Found
6. Preventive Measures and Monitoring
Regular security baselines and patch management are essential for preventing this issue. Consider adding checks to your CI/CD pipeline to identify similar vulnerabilities.
- Baselines: Update security baselines or policies to include requirements for input validation and secure coding practices.
- Pipelines: Add Static Application Security Testing (SAST) tools to your CI/CD pipeline to scan code for potential XSS vulnerabilities.
- Asset and patch process: Implement a regular patch review cycle, prioritising security updates from vendors like WebCamSoft.
7. Risks, Side Effects, and Roll Back
Disabling the CGI application may impact functionality if it is required for other features. A roll back involves re-enabling the script in the web server configuration.
- Risk or side effect 1: Disabling the CGI application could break existing functionality that relies on it.
- Risk or side effect 2: Incorrectly configuring the webserver may cause other services to fail.
- Roll back: Step 1: Restore the original web server configuration file from backup. Step 2: Restart the web server service.
8. References and Resources
- Vendor advisory or bulletin: No current vendor advisory available.
- NVD or CVE entry: https://securitytracker.com/id?1010824
- Product or platform documentation relevant to the fix: No current documentation available.