CVE-2023-2454
📋 TL;DR
CVE-2023-2454 is a PostgreSQL vulnerability where the schema_element function can bypass protective search_path changes, allowing authenticated attackers with elevated database privileges to execute arbitrary code. This affects PostgreSQL instances where untrusted users have CREATE privileges on schemas. Database administrators and applications using PostgreSQL with multi-tenant schemas are primarily affected.
💻 Affected Systems
- PostgreSQL
📦 What is this software?
Fedora by Fedoraproject
Postgresql by Postgresql
Postgresql by Postgresql
Postgresql by Postgresql
Postgresql by Postgresql
Postgresql by Postgresql
⚠️ Risk & Real-World Impact
Worst Case
Full database compromise leading to data exfiltration, privilege escalation to operating system level, and complete system takeover.
Likely Case
Unauthorized data access, privilege escalation within the database, and potential lateral movement to connected systems.
If Mitigated
Limited impact due to proper privilege separation, network segmentation, and minimal attack surface exposure.
🎯 Exploit Status
Exploitation requires authenticated database access with specific privileges; proof-of-concept code has been published.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: PostgreSQL 15.3, 14.8, 13.11, 12.15, and 11.20
Vendor Advisory: https://www.postgresql.org/support/security/CVE-2023-2454/
Restart Required: Yes
Instructions:
1. Backup your database. 2. Stop PostgreSQL service. 3. Upgrade to patched version using your package manager (apt/yum). 4. Start PostgreSQL service. 5. Verify upgrade with SELECT version();
🔧 Temporary Workarounds
Revoke CREATE privileges
allRemove CREATE privilege from untrusted users on all schemas to prevent exploitation.
REVOKE CREATE ON SCHEMA schema_name FROM username;
Restrict search_path
allSet search_path to exclude untrusted schemas in session configuration.
SET search_path TO pg_catalog, public;
🧯 If You Can't Patch
- Implement strict network access controls to limit PostgreSQL port exposure
- Apply principle of least privilege by auditing and reducing CREATE privileges
🔍 How to Verify
Check if Vulnerable:
Check PostgreSQL version with SELECT version(); and compare against affected versions list.Check Version:
SELECT version();Verify Fix Applied:
Verify version is 15.3, 14.8, 13.11, 12.15, 11.20 or later using SELECT version();📡 Detection & Monitoring
Log Indicators:
- Unusual CREATE FUNCTION or CREATE SCHEMA statements from non-admin users
- Multiple failed privilege escalation attempts in logs
Network Indicators:
- Unexpected connections to PostgreSQL port from unauthorized sources
- Suspicious query patterns in database traffic
SIEM Query:
source="postgresql.log" AND ("CREATE FUNCTION" OR "CREATE SCHEMA") AND user!="postgres"🔗 References
- https://access.redhat.com/security/cve/CVE-2023-2454
- https://security.netapp.com/advisory/ntap-20230706-0006/
- https://www.postgresql.org/support/security/CVE-2023-2454/
- https://access.redhat.com/security/cve/CVE-2023-2454
- https://security.netapp.com/advisory/ntap-20230706-0006/
- https://www.postgresql.org/support/security/CVE-2023-2454/
