1. Introduction
The Target Information vulnerability publishes details about the starting URL used in a scan. This can help attackers understand your network and identify potential targets. Systems that are scanned, particularly web servers and applications accessible from the internet, are usually affected. A successful exploit could lead to information disclosure impacting confidentiality.
2. Technical Explanation
This vulnerability occurs because the scan tool reveals information about the target URL during operation. An attacker can simply observe this information to gain insight into your infrastructure. There is no specific CVE, CVSS or CWE associated with this issue as it relates to the scan process itself rather than a flaw in a product. For example, an attacker could use a network monitoring tool like Wireshark to capture the initial URL used during a vulnerability scan and identify the target system.
- Root cause: The scan tool outputs information about the target URL.
- Exploit mechanism: An attacker passively observes the scan traffic to determine the target URL.
- Scope: Any web server or application scanned by a vulnerability scanner is affected.
3. Detection and Assessment
Confirming exposure involves reviewing network traffic during scans. A thorough method would be to analyse full packet captures.
- Quick checks: Review scan logs for the initial target URL used in each scan.
- Scanning: No specific scanner signatures are available as this is a characteristic of the scanning process itself.
- Logs and evidence: Examine network traffic capture files (PCAP) for the initial URL request made by the vulnerability scanner.
tcpdump -i eth0 host -n | grep "http" 4. Solution / Remediation Steps
The following steps aim to minimise information disclosure during scans.
4.1 Preparation
- Ensure you have access to the scan tool’s configuration files. A roll back plan is to restore from the previous snapshot if issues occur.
- A change window may be needed depending on service impact, and approval should come from the IT security team.
4.2 Implementation
- Step 1: Configure the scan tool to mask or obfuscate the target URL in its output logs.
- Step 2: If possible, configure the scanner to use a proxy server that hides the original target URL from external observation.
4.3 Config or Code Example
Before
# Scan configuration - showing full URL
target_url = "https://example.com/sensitive-data"
log_level = "debug"After
# Scan configuration - masking the URL
target_url = "https://[REDACTED]"
log_level = "info"4.4 Security Practices Relevant to This Vulnerability
Practices that directly address this vulnerability type include minimising information disclosure and least privilege.
- Practice 1: Least privilege access for the scan tool itself, limiting its ability to write detailed logs.
- Practice 2: Input validation on any user-supplied data used in scan configurations to prevent injection of sensitive URLs.
4.5 Automation (Optional)
No automation is recommended as this requires specific configuration changes within the scanning tool, which varies between products.
5. Verification / Validation
- Post-fix check: Review scan logs to confirm that the target URL is masked or obfuscated as configured.
- Re-test: Re-run a scan and verify that the initial target URL is not visible in network captures.
- Monitoring: Monitor scan logs for unexpected output or information disclosure patterns (example only).
tcpdump -i eth0 host -n | grep "https://[REDACTED]" 6. Preventive Measures and Monitoring
Relevant measures include updating security baselines and reviewing scan configurations regularly for example.
- Baselines: Update a security baseline to require masking of sensitive information in scan logs.
- Asset and patch process: Review scan tool configurations quarterly as part of the asset management process.
7. Risks, Side Effects, and Roll Back
Potential risks include scan failures if masking is incorrectly configured. Roll back involves restoring the original scan configuration.
- Roll back: Restore the previous scan configuration file from backup.
8. References and Resources
No specific references are available for this vulnerability as it relates to scan tool behaviour.
- Vendor advisory or bulletin: N/A
- NVD or CVE entry: N/A
- Product or platform documentation relevant to the fix: Refer to your scanning tool’s documentation for configuration options.