CVE-2025-21579
📋 TL;DR
This vulnerability in MySQL Server allows high-privileged attackers with network access to cause a denial of service (DoS) by crashing or hanging the server. It affects MySQL versions 8.0.0-8.0.41, 8.4.0-8.4.4, and 9.0.0-9.2.0. Attackers need administrative database privileges but can exploit it remotely via multiple protocols.
💻 Affected Systems
- Oracle MySQL Server
📦 What is this software?
⚠️ Risk & Real-World Impact
Worst Case
Complete unavailability of MySQL Server leading to application downtime and service disruption.
Likely Case
Targeted DoS attacks against vulnerable MySQL instances by malicious insiders or compromised admin accounts.
If Mitigated
Limited impact due to proper access controls and network segmentation preventing unauthorized admin access.
🎯 Exploit Status
CVSS indicates 'easily exploitable' but requires high privileges. No public exploit code identified in references.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Versions after 8.0.41, 8.4.4, and 9.2.0 (check Oracle's Critical Patch Update for exact fixed versions)
Vendor Advisory: https://www.oracle.com/security-alerts/cpuapr2025.html
Restart Required: Yes
Instructions:
1. Review Oracle's April 2025 Critical Patch Update advisory. 2. Identify fixed versions for your MySQL release. 3. Apply patches through your standard update process. 4. Restart MySQL service after patching.
🔧 Temporary Workarounds
Restrict Administrative Access
allLimit network access to MySQL administrative interfaces and reduce number of high-privilege accounts.
# Review and remove unnecessary admin accounts
SELECT user, host FROM mysql.user WHERE Super_priv = 'Y';
# Restrict network access in my.cnf
bind-address = internal_ip_only
🧯 If You Can't Patch
- Implement strict network segmentation to isolate MySQL servers from untrusted networks
- Enforce principle of least privilege for database accounts and monitor admin activity
🔍 How to Verify
Check if Vulnerable:
Check MySQL version: SELECT VERSION(); and compare against affected ranges.Check Version:
mysql -e "SELECT VERSION();"Verify Fix Applied:
Verify version is above affected ranges and check Oracle advisory for specific fixed versions.📡 Detection & Monitoring
Log Indicators:
- Unexpected MySQL crashes or hangs
- Multiple connection attempts from admin accounts followed by service disruption
Network Indicators:
- Unusual traffic patterns to MySQL administrative ports from unexpected sources
SIEM Query:
source="mysql.log" ("crash" OR "hang" OR "shutdown") AND (user="root" OR Super_priv="Y")