1. Introduction
The Abyss Web Server GET Request Multiple Vulnerabilities affect the Abyss Web Server software. These vulnerabilities could allow an attacker to execute arbitrary code on a vulnerable system, and inject malicious data into server responses leading to cross-site scripting attacks. This impacts confidentiality, integrity, and availability of affected systems. Systems running Abyss Web Server versions earlier than 1.1.6 are typically affected.
2. Technical Explanation
The remote Abyss Web server is vulnerable due to a buffer overflow in versions prior to 1.1.6. This allows an attacker to potentially execute arbitrary code on the host system by sending a specially crafted GET request. Additionally, malicious data can be injected into server response headers via a crafted GET request, enabling cross-site scripting (XSS) attacks. CVE-2003-1337 describes this vulnerability.
- Root cause: A buffer overflow exists in the handling of incoming requests.
- Exploit mechanism: An attacker sends a malicious HTTP GET request designed to overwrite memory buffers, potentially leading to code execution or XSS. For example, sending an overly long URL string could trigger the buffer overflow.
- Scope: Abyss Web Server versions earlier than 1.1.6 are affected.
3. Detection and Assessment
To confirm vulnerability, check the installed version of Abyss Web Server. A thorough assessment involves attempting to exploit the buffer overflow or inject malicious data.
- Quick checks: Check the server banner or configuration files for the version number.
- Scanning: Nessus plugin ID 30968 may detect this vulnerability as an example.
- Logs and evidence: Examine web server logs for unusual request lengths or patterns indicative of exploitation attempts.
http -v GET / HTTP/1.1 Host: vulnerable-server.example.com4. Solution / Remediation Steps
Upgrade to Abyss 1.1.6 or a newer version to fix the problem.
4.1 Preparation
- Ensure you have downloaded the correct upgrade package for your platform. Change windows may be needed depending on business impact.
4.2 Implementation
- Step 1: Download Abyss Web Server version 1.1.6 or newer from a trusted source.
- Step 2: Stop the Abyss Web Server service.
- Step 3: Install the new version of Abyss Web Server, following the vendor’s instructions.
- Step 4: Restore your backed-up configuration files if needed.
- Step 5: Start the Abyss Web Server service.
4.3 Config or Code Example
Before
After
4.4 Security Practices Relevant to This Vulnerability
Several security practices can help prevent this type of vulnerability. Patch cadence ensures systems are up-to-date with the latest security fixes, reducing exposure to known vulnerabilities. Input validation prevents malicious data from being processed by the server.
- Practice 1: Implement a regular patch management process to ensure timely updates.
- Practice 2: Use input validation techniques to sanitize incoming requests and prevent buffer overflows or XSS attacks.
4.5 Automation (Optional)
5. Verification / Validation
Confirm the upgrade was successful by checking the installed version. Re-test using the earlier detection method and perform a simple service smoke test.
- Post-fix check: Check the server banner or configuration files to confirm Abyss Web Server 1.1.6 or newer is running.
- Re-test: Repeat the quick check from section 3 to verify the vulnerability is no longer present.
- Smoke test: Verify that you can access a basic webpage served by the web server.
http -v GET / HTTP/1.1 Host: vulnerable-server.example.com6. Preventive Measures and Monitoring
Update security baselines to include the latest Abyss Web Server version requirements. Implement checks in CI or deployment pipelines to prevent deploying older, vulnerable versions.
- Baselines: Update your server baseline configuration to require Abyss Web Server 1.1.6 or newer.
7. Risks, Side Effects, and Roll Back
Upgrading may cause temporary service disruption. Ensure you have a roll back plan in place.
- Risk or side effect 1: Service interruption during the upgrade process. Mitigation: Schedule upgrades during off-peak hours.
- Roll back: Restore the backed-up configuration files and restart the previous version of Abyss Web Server.
8. References and Resources
- Vendor advisory or bulletin: https://seclists.org/bugtraq/2003/Jun/253
- NVD or CVE entry: CVE-2003-1337