CVE-2022-23944 Overview
CVE-2022-23944 is an authentication bypass vulnerability affecting Apache ShenYu, a high-performance, cross-language, responsive API gateway. The vulnerability allows unauthenticated users to access the /plugin API endpoint without proper authentication, potentially exposing sensitive plugin management functionality to unauthorized actors.
Critical Impact
Unauthenticated attackers can access the plugin API, enabling unauthorized reading and modification of plugin configurations, which could lead to service disruption or further compromise of the API gateway infrastructure.
Affected Products
- Apache ShenYu 2.4.0
- Apache ShenYu 2.4.1
Discovery Timeline
- 2022-01-25 - CVE-2022-23944 published to NVD
- 2024-11-21 - Last updated in NVD database
Technical Details for CVE-2022-23944
Vulnerability Analysis
This vulnerability represents a critical authentication bypass flaw (CWE-862: Missing Authorization, CWE-306: Missing Authentication for Critical Function) in Apache ShenYu's administrative API. The /plugin endpoint, which should be protected by authentication mechanisms, is accessible without any credentials. This design flaw allows remote attackers to interact with the plugin management interface directly over the network.
The vulnerability enables both read and write operations on plugin configurations without requiring authentication. Attackers exploiting this flaw can enumerate installed plugins, modify plugin settings, potentially disable security plugins, or inject malicious configurations into the gateway's plugin chain.
Root Cause
The root cause of CVE-2022-23944 is a missing authentication check on the /plugin API endpoint in Apache ShenYu. The affected versions (2.4.0 and 2.4.1) fail to enforce proper access controls before processing requests to this sensitive endpoint. This likely resulted from an oversight in the security implementation where the authentication filter or interceptor was not properly configured for the plugin management routes.
Attack Vector
The attack vector for this vulnerability is network-based and requires no user interaction or prior authentication. An attacker with network access to the Apache ShenYu admin interface can directly send HTTP requests to the /plugin endpoint to:
- Retrieve sensitive plugin configuration data
- Modify existing plugin settings
- Potentially disable critical security plugins
- Inject malicious configurations that could affect API gateway behavior
The attack can be executed remotely without any special privileges, making it particularly dangerous for internet-facing ShenYu deployments. The vulnerability affects both the confidentiality and integrity of the system, as attackers can read and modify plugin configurations.
Detection Methods for CVE-2022-23944
Indicators of Compromise
- Unexpected HTTP requests to /plugin API endpoints from unknown or external IP addresses
- Authentication logs showing plugin API access without corresponding successful login events
- Unusual modifications to plugin configurations without authorized administrative actions
- Network traffic patterns showing enumeration attempts against the ShenYu admin interface
Detection Strategies
- Monitor web server access logs for unauthenticated requests to /plugin endpoints
- Implement network intrusion detection rules to alert on direct access attempts to the ShenYu admin API from untrusted networks
- Review Apache ShenYu configuration change logs for unauthorized plugin modifications
- Deploy web application firewall (WAF) rules to block unauthenticated access to administrative endpoints
Monitoring Recommendations
- Enable detailed logging for all admin API endpoints including /plugin
- Set up alerts for any plugin configuration changes outside of maintenance windows
- Monitor for reconnaissance activities targeting ShenYu administrative interfaces
- Implement anomaly detection for unusual API access patterns to administrative endpoints
How to Mitigate CVE-2022-23944
Immediate Actions Required
- Upgrade Apache ShenYu to a version higher than 2.4.1 that addresses this vulnerability
- Restrict network access to the ShenYu admin interface using firewall rules or network segmentation
- Implement authentication at the network layer (VPN, IP allowlisting) as an interim measure
- Audit plugin configurations for any unauthorized changes
Patch Information
Apache has addressed this vulnerability in subsequent releases of Apache ShenYu. Organizations should consult the Apache Mailing List Thread and OpenWall OSS-Security Advisory for detailed patch information and upgrade instructions.
Workarounds
- Place the Apache ShenYu admin interface behind a reverse proxy that enforces authentication
- Implement IP-based access control lists to restrict admin interface access to trusted management networks only
- Use network segmentation to isolate the ShenYu admin interface from untrusted network segments
- Deploy a web application firewall (WAF) to enforce authentication requirements on the /plugin endpoint
# Example: Restrict access to ShenYu admin interface using iptables
# Only allow connections from trusted management network (10.0.0.0/24)
iptables -A INPUT -p tcp --dport 9095 -s 10.0.0.0/24 -j ACCEPT
iptables -A INPUT -p tcp --dport 9095 -j DROP
Disclaimer: This content was generated using AI. While we strive for accuracy, please verify critical information with official sources.
