CVE-2015-0241
📋 TL;DR
This vulnerability in PostgreSQL's to_char function allows remote authenticated users to trigger buffer over-reads or buffer overflows via specially crafted numeric or timestamp formatting templates. This can lead to denial of service (crash) or potentially arbitrary code execution. Affected users are those running vulnerable PostgreSQL versions with authenticated database access.
💻 Affected Systems
- PostgreSQL
📦 What is this software?
Postgresql by Postgresql
Postgresql by Postgresql
Postgresql by Postgresql
Postgresql by Postgresql
Postgresql by Postgresql
⚠️ Risk & Real-World Impact
Worst Case
Remote authenticated attacker gains arbitrary code execution with database privileges, potentially leading to full system compromise.
Likely Case
Denial of service through database crash, disrupting application availability.
If Mitigated
With proper network segmentation and least privilege access, impact limited to database service disruption.
🎯 Exploit Status
Exploitation requires authenticated database access and knowledge of vulnerable to_char function usage. Buffer overflow exploitation requires additional memory manipulation skills.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: PostgreSQL 9.0.19, 9.1.15, 9.2.10, 9.3.6, or 9.4.1
Vendor Advisory: http://www.postgresql.org/about/news/1569/
Restart Required: Yes
Instructions:
1. Backup database. 2. Stop PostgreSQL service. 3. Upgrade to patched version. 4. Restart PostgreSQL service. 5. Verify functionality.
🔧 Temporary Workarounds
Restrict Database Access
allLimit authenticated user access to only necessary accounts and implement network access controls.
# Example: Restrict pg_hba.conf entries
host all all 192.168.1.0/24 md5
Application-Level Input Validation
allValidate and sanitize all user inputs passed to to_char function in application code.
🧯 If You Can't Patch
- Implement strict network segmentation to isolate PostgreSQL from untrusted networks
- Apply principle of least privilege to database user accounts and monitor for suspicious queries
🔍 How to Verify
Check if Vulnerable:
Check PostgreSQL version with: SELECT version(); and compare against affected versions.Check Version:
SELECT version();Verify Fix Applied:
Verify version is 9.0.19, 9.1.15, 9.2.10, 9.3.6, 9.4.1 or higher with: SELECT version();📡 Detection & Monitoring
Log Indicators:
- PostgreSQL crash logs
- Segmentation fault errors in PostgreSQL logs
- Unusual to_char function calls with large numeric inputs
Network Indicators:
- Database connection attempts followed by crash
- Repeated authentication attempts to PostgreSQL
SIEM Query:
source="postgresql.log" AND ("segmentation fault" OR "crash" OR "to_char")🔗 References
- http://www.debian.org/security/2015/dsa-3155
- http://www.postgresql.org/about/news/1569/
- http://www.postgresql.org/docs/9.4/static/release-9-4-1.html
- http://www.postgresql.org/docs/current/static/release-9-0-19.html
- http://www.postgresql.org/docs/current/static/release-9-1-15.html
- http://www.postgresql.org/docs/current/static/release-9-2-10.html
- http://www.postgresql.org/docs/current/static/release-9-3-6.html
- http://www.debian.org/security/2015/dsa-3155
- http://www.postgresql.org/about/news/1569/
- http://www.postgresql.org/docs/9.4/static/release-9-4-1.html
- http://www.postgresql.org/docs/current/static/release-9-0-19.html
- http://www.postgresql.org/docs/current/static/release-9-1-15.html
- http://www.postgresql.org/docs/current/static/release-9-2-10.html
- http://www.postgresql.org/docs/current/static/release-9-3-6.html
