CVE-2021-40331
📋 TL;DR
This vulnerability in Apache Ranger Hive Plugin allows users with only SELECT privilege on a database to alter table ownership in Hive when the plugin is enabled. This affects Apache Ranger Hive Plugin versions 2.0.0 through 2.3.0, potentially enabling privilege escalation and unauthorized data access.
💻 Affected Systems
- Apache Ranger Hive Plugin
📦 What is this software?
Ranger by Apache
⚠️ Risk & Real-World Impact
Worst Case
An attacker with SELECT privilege could take ownership of critical tables, modify data, grant themselves additional privileges, or disrupt Hive operations across the entire database.
Likely Case
Malicious or compromised users with legitimate SELECT access could escalate privileges to modify or delete data they shouldn't have access to, potentially leading to data integrity issues.
If Mitigated
With proper access controls and monitoring, impact is limited to users who already have SELECT access, but they could still perform unauthorized ownership changes.
🎯 Exploit Status
Exploitation requires authenticated access with SELECT privilege. The vulnerability is in the permission validation logic of the Ranger plugin.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: 2.4.0 or later
Vendor Advisory: https://lists.apache.org/thread/s68yls6cnkdmzn1k4hqt50vs6wjvt2rn
Restart Required: Yes
Instructions:
1. Download Apache Ranger 2.4.0 or later. 2. Stop Hive services. 3. Replace the Ranger Hive Plugin with the patched version. 4. Restart Hive services. 5. Verify the plugin version and functionality.
🔧 Temporary Workarounds
Disable Ranger Hive Plugin
allTemporarily disable the vulnerable plugin until patching can be completed.
# Remove or rename the Ranger plugin JAR files from Hive classpath
# Example: mv /path/to/ranger-hive-plugin*.jar /path/to/ranger-hive-plugin*.jar.disabled
Restrict SELECT Privileges
allTighten access controls to minimize users with SELECT privilege on sensitive databases.
# Use Ranger policies to restrict SELECT access
# Review and revoke unnecessary SELECT privileges
🧯 If You Can't Patch
- Implement strict monitoring of Hive ownership changes and ALTER TABLE operations.
- Enforce least privilege access and regularly audit user permissions in Ranger policies.
🔍 How to Verify
Check if Vulnerable:
Check the Ranger Hive Plugin version. If version is between 2.0.0 and 2.3.0 inclusive, the system is vulnerable.Check Version:
Check the plugin JAR file version or Ranger admin console for plugin version information.Verify Fix Applied:
Verify the plugin version is 2.4.0 or later and test that users with only SELECT privilege cannot alter table ownership.📡 Detection & Monitoring
Log Indicators:
- Hive audit logs showing ALTER TABLE OWNER commands from users with only SELECT privilege
- Ranger plugin logs showing permission validation failures or bypasses
Network Indicators:
- Unusual patterns of ALTER TABLE commands from users with limited privileges
SIEM Query:
source="hive_audit_logs" AND command="ALTER TABLE" AND (user_privileges="SELECT" OR user_privileges="select")