1. Introduction
Adobe InDesign Server is vulnerable to a RunScript arbitrary command execution attack. This means an attacker can remotely execute commands on systems running the service, potentially gaining control of the server. Systems commonly affected are those hosting web services that use Adobe InDesign Server for document processing. A successful exploit could compromise confidentiality, integrity, and availability of the system.
2. Technical Explanation
The vulnerability occurs because the SOAP service in Adobe InDesign Server processes RunScript requests without authentication. This allows a remote attacker to execute arbitrary VBScript on Windows or AppleScript on macOS. An attacker could send a specially crafted request to the server, triggering the execution of malicious code.
- Root cause: Lack of authentication for the RunScript method in the SOAP service.
- Exploit mechanism: An unauthenticated attacker sends a malicious SOAP request containing VBScript or AppleScript code that is then executed by the server. For example, an attacker could send a request to execute a command to create a new user account on the system.
- Scope: Adobe InDesign Server running with the SOAP service enabled.
3. Detection and Assessment
To confirm vulnerability, check the version of Adobe InDesign Server installed and verify if the SOAP service is enabled.
- Quick checks: Check the version using the command line interface or through the administrative console.
- Scanning: Nessus plugin ID 56574 can detect this vulnerability. This is an example only, other scanners may also provide detection capabilities.
- Logs and evidence: Look for suspicious SOAP requests in the server logs. The specific log file location varies depending on the operating system and configuration.
4. Solution / Remediation Steps
There is currently no known solution for this vulnerability. Mitigation focuses on restricting access and monitoring for suspicious activity.
4.1 Preparation
- Services: No services need to be stopped.
- Roll back plan: Restore the system from the pre-change backup if issues occur. Change windows may be required depending on business impact.
4.2 Implementation
- Step 1: Restrict access to the InDesign Server SOAP service using firewall rules, allowing only trusted hosts to connect.
- Step 2: Implement robust monitoring of server logs for suspicious activity related to SOAP requests.
4.3 Config or Code Example
Before
After
4.4 Security Practices Relevant to This Vulnerability
Practices that directly address this vulnerability type include least privilege and network segmentation.
- Practice 1: Least privilege – Limit user accounts with access to the server to only those necessary for operation, reducing potential impact if compromised.
- Practice 2: Network segmentation – Isolate the InDesign Server on a separate network segment to limit lateral movement in case of exploitation.
4.5 Automation (Optional)
No automation is available at this time due to lack of a direct fix.
5. Verification / Validation
Verify that access to the SOAP service is restricted and monitor logs for any unauthorized attempts.
- Post-fix check: Attempt to connect to the SOAP service from an untrusted host; connection should be refused.
- Re-test: Review server logs for failed connection attempts from untrusted hosts.
- Smoke test: Verify that authorized users can still access and use other InDesign Server features.
- Monitoring: Monitor server logs for suspicious SOAP requests, looking for unusual patterns or payloads.
6. Preventive Measures and Monitoring
Update security baselines to include restrictions on access to sensitive services like the InDesign Server SOAP service. Implement logging and monitoring for suspicious activity.
- Baselines: Update a security baseline or policy to enforce least privilege and network segmentation.
- Pipelines: Add checks in deployment pipelines to ensure that unnecessary services are disabled.
- Asset and patch process: Maintain a regular review cycle for installed software and apply patches promptly when available.
7. Risks, Side Effects, and Roll Back
- Risk or side effect 1: Legitimate users may be unable to connect if firewall rules are too restrictive.
- Risk or side effect 2: Incorrectly configured monitoring may result in false positives.
- Roll back: Remove the firewall rule and restore default network settings.
8. References and Resources
- Vendor advisory or bulletin: http://www.securityfocus.com/bid/56574
- NVD or CVE entry: Not available at this time.
- Product or platform documentation relevant to the fix: https://helpx.adobe.com/indesign-server/using/soap-service.html