CVE-2020-36922: Sony BRAVIA Information Disclosure Flaw

CVE-2020-36922 Overview

CVE-2020-36922 is an information disclosure vulnerability affecting Sony BRAVIA Digital Signage version 1.7.8. This vulnerability allows unauthenticated attackers to access sensitive system details through exposed API endpoints without any authentication. Attackers can retrieve network interface information, server configurations, and system metadata by sending HTTP requests to the unauthenticated system API.

The vulnerability is classified as CWE-497 (Exposure of Sensitive System Information to an Unauthorized Control Sphere), indicating that the application inadvertently exposes internal system details that could be leveraged for further attacks or reconnaissance.

Critical Impact

Unauthenticated remote attackers can access sensitive system configuration data, network interface details, and metadata from Sony BRAVIA Digital Signage installations, potentially enabling reconnaissance for follow-up attacks.

Affected Products

• Sony BRAVIA Digital Signage version 1.7.8

Discovery Timeline

• 2026-01-06 - CVE-2020-36922 published to NVD
• 2026-01-08 - Last updated in NVD database

Technical Details for CVE-2020-36922

Vulnerability Analysis

This vulnerability stems from improper access control on the system API endpoints within the Sony BRAVIA Digital Signage application. The application exposes sensitive system information through API endpoints that lack proper authentication mechanisms. When an attacker sends requests to these endpoints, the application returns detailed system information including network interface configurations, server settings, and system metadata without verifying the identity or authorization of the requester.

The network-based attack vector means this vulnerability can be exploited remotely by any attacker who has network access to the vulnerable device. No user interaction is required, and no prior authentication or privileges are needed to exploit this flaw. The exposure of this information could enable attackers to map network infrastructure, identify additional attack surfaces, and gather intelligence for more sophisticated attacks against the organization.

Root Cause

The root cause of CVE-2020-36922 is the lack of authentication enforcement on sensitive API endpoints within the Sony BRAVIA Digital Signage application. The system API was designed to provide system information for administrative purposes but was deployed without proper access controls, allowing any network-reachable client to query these endpoints and retrieve sensitive data.

Attack Vector

The attack vector is network-based and requires no authentication. An attacker with network access to a Sony BRAVIA Digital Signage installation running version 1.7.8 can send HTTP requests to the exposed system API endpoints. The vulnerable endpoints return sensitive information including:

• Network interface configurations
• Server configuration details
• System metadata and environment information

The attack can be executed using standard HTTP client tools or web browsers, making it trivially easy to exploit once the vulnerable endpoint is discovered.

Detection Methods for CVE-2020-36922

Indicators of Compromise

• Unusual HTTP requests to system API endpoints from unauthorized IP addresses
• Increased reconnaissance traffic targeting BRAVIA Digital Signage management interfaces
• Logs showing repeated API queries for system information from external sources

Detection Strategies

• Monitor web server logs for unauthenticated requests to sensitive API endpoints
• Implement network intrusion detection rules to identify enumeration attempts against BRAVIA Digital Signage systems
• Review access logs for patterns consistent with automated scanning or reconnaissance activity

Monitoring Recommendations

• Enable verbose logging on Sony BRAVIA Digital Signage installations
• Configure alerting for API access attempts from untrusted network segments
• Regularly audit network traffic to digital signage infrastructure for anomalous patterns

How to Mitigate CVE-2020-36922

Immediate Actions Required

• Isolate Sony BRAVIA Digital Signage systems from untrusted networks
• Implement network-level access controls to restrict API endpoint access to authorized management systems
• Review and audit any systems that may have been exposed to determine if information disclosure occurred

Patch Information

Organizations should check for updated firmware and software versions from Sony. Consult the Sony Pro Bravia Resource and the Sony Bravia Signage Software page for the latest security updates and patch availability.

Additional technical details about this vulnerability are available from the VulnCheck Sony Bravia Advisory and the Zero Science Vulnerability Report.

Workarounds

• Deploy network segmentation to isolate digital signage systems from general network access
• Implement firewall rules to restrict access to the BRAVIA Digital Signage management interface to specific trusted IP addresses
• Use a reverse proxy with authentication requirements in front of the digital signage management interface
• Disable or block access to the vulnerable API endpoints at the network level if not operationally required

# Example firewall rule to restrict access to digital signage management interface
# Allow only trusted management subnet (adjust IP ranges as appropriate)
iptables -A INPUT -p tcp --dport 80 -s 10.0.100.0/24 -j ACCEPT
iptables -A INPUT -p tcp --dport 80 -j DROP