CVE-2024-37820
📋 TL;DR
This vulnerability in PingCAP TiDB v8.2.0-alpha-216-gfe5858b allows attackers to cause a denial of service by triggering a nil pointer dereference in the expression.inferCollation function. It affects TiDB database deployments running the vulnerable version. The crash can disrupt database availability but does not allow data theft or remote code execution.
💻 Affected Systems
- PingCAP TiDB
⚠️ Manual Verification Required
This CVE does not have specific version information in our database, so automatic vulnerability detection cannot determine if your system is affected.
Why? The CVE database entry doesn't specify which versions are vulnerable (no version ranges provided by the vendor/NVD).
🔒 Custom verification scripts are available for registered users. Sign up free to download automated test scripts.
- Review the CVE details at NVD
- Check vendor security advisories for your specific version
- Test if the vulnerability is exploitable in your environment
- Consider updating to the latest version as a precaution
⚠️ Risk & Real-World Impact
Worst Case
Complete database service outage leading to application downtime and business disruption
Likely Case
Service crash requiring restart, causing temporary unavailability
If Mitigated
Minimal impact if proper monitoring and restart automation are in place
🎯 Exploit Status
Exploit requires database access/authentication; crash trigger is documented in GitHub issues
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Fixed in later versions; upgrade to stable release
Vendor Advisory: https://github.com/pingcap/tidb/issues/53580
Restart Required: Yes
Instructions:
1. Check current TiDB version
2. Upgrade to latest stable release
3. Restart TiDB services
4. Verify fix with test queries
🔧 Temporary Workarounds
Restrict database access
linuxLimit network access to TiDB to trusted sources only
iptables -A INPUT -p tcp --dport 4000 -s trusted_ip -j ACCEPT
iptables -A INPUT -p tcp --dport 4000 -j DROP
🧯 If You Can't Patch
- Implement strict network segmentation to isolate TiDB from untrusted networks
- Deploy monitoring with automatic restart for crash detection
🔍 How to Verify
Check if Vulnerable:
Check TiDB version: SELECT VERSION(); should not return v8.2.0-alpha-216-gfe5858bCheck Version:
mysql -h host -P port -u user -p -e 'SELECT VERSION();'Verify Fix Applied:
Test with queries that previously triggered the crash; verify service remains stable📡 Detection & Monitoring
Log Indicators:
- Panic logs containing 'nil pointer dereference'
- TiDB process crashes
- Error messages mentioning expression.inferCollation
Network Indicators:
- Unusual database query patterns
- Multiple connection attempts to trigger crash
SIEM Query:
source="tidb.log" AND "panic" AND "nil pointer"