CVE-2024-57620

Executive Summary

CVE-2024-57620 is a denial-of-service (DoS) vulnerability in the trimchars component of MonetDB Server v11.47.11. An attacker can exploit this flaw by sending crafted SQL statements, causing the database server to crash or become unresponsive. The vulnerability has a CVSS score of 0.0 (likely unassigned or placeholder), but the EPSS score of 0.0% suggests low exploitation activity in the wild. No public exploit code or patch is currently available.

CVSS Breakdown & Threat Level

• CVSS Score: 0.0 (Unassigned / Placeholder)
• Attack Vector: Network (likely)
• Attack Complexity: Low (likely)
• Privileges Required: None (likely)
• User Interaction: None (likely)
• Scope: Unchanged
• Confidentiality Impact: None
• Integrity Impact: None
• Availability Impact: High
• Threat Level: Medium (due to DoS potential and lack of patch)

Deep Dive & Mechanics

The trimchars function in MonetDB is used to remove specified characters from strings. The vulnerability arises from improper input validation or memory handling when processing specially crafted SQL statements that invoke trimchars with malicious parameters. This can lead to a segmentation fault, infinite loop, or memory exhaustion, resulting in a denial of service.

The exact root cause is unknown without a patch or detailed analysis, but typical DoS vulnerabilities in database functions involve:

• Buffer overflows
• Integer overflows
• Null pointer dereferences
• Uncontrolled recursion

Vulnerable vs. Patched Code

No patch is available. The vulnerable code resides in the trimchars function within MonetDB Server v11.47.11. A patched version would likely include:

• Input length validation
• Bounds checking
• Safe memory allocation

Exploitation & Lab Setup

Red Team

1. Setup: Deploy MonetDB Server v11.47.11 in a controlled environment.
2. Craft Payload: Create a SQL statement that abuses trimchars with a long string or special characters.

   SELECT TRIM(LEADING 'a' FROM REPEAT('a', 1000000));
   

3. Execute: Send the crafted SQL to the server via a client or script.

   mclient -d mydb -s "SELECT TRIM(LEADING 'a' FROM REPEAT('a', 1000000));"
   

4. Observe: Monitor server logs for crashes or unresponsiveness.

Blue Team

1. Monitor: Watch for unusual SQL queries with excessive string lengths or repeated calls to trimchars.
2. Rate Limit: Implement query rate limiting and input validation at the application layer.
3. WAF Rules: Deploy Web Application Firewall rules to block suspicious SQL patterns.
4. Backup: Ensure regular backups and failover mechanisms are in place.

Indicators of Compromise (IOCs)

• Log Entries: Repeated SQL errors related to trimchars or memory allocation failures.
• Network Traffic: Unusual SQL queries with long strings or special characters.
• System Metrics: Sudden CPU/memory spikes followed by database crash.

Detection Engineering

YARA Rule

rule CVE_2024_57620_trimchars_DoS {
    meta:
        description = "Detects potential exploitation of CVE-2024-57620 via crafted SQL"
        author = "Valters IT"
        date = "2025-04-10"
    strings:
        $sql1 = "TRIM" nocase
        $sql2 = "LEADING" nocase
        $sql3 = "TRAILING" nocase
        $sql4 = "BOTH" nocase
        $long = /[a-zA-Z0-9]{1000,}/
    condition:
        all of ($sql*) and #long > 0
}

Sigma Rule

title: CVE-2024-57620 MonetDB trimchars DoS
id: 12345678-1234-1234-1234-123456789012
status: experimental
description: Detects SQL queries exploiting trimchars vulnerability
author: Valters IT
logsource:
    category: application
    product: monetdb
detection:
    selection:
        query|contains: 
            - 'TRIM'
            - 'LEADING'
            - 'TRAILING'
            - 'BOTH'
        query|re: '[a-zA-Z0-9]{1000,}'
    condition: selection
falsepositives:
    - Legitimate large string operations
level: high

Suricata Rule

alert tcp $EXTERNAL_NET any -> $HOME_NET 50000 (msg:"CVE-2024-57620 MonetDB trimchars DoS"; flow:to_server,established; content:"TRIM"; nocase; content:"LEADING|20|"; distance:0; within:100; pcre:"/[a-zA-Z0-9]{1000,}/"; classtype:attempted-dos; sid:1000001; rev:1;)

Remediation & Mitigation

• Immediate: Disable or restrict access to the trimchars function if not needed.
• Short-term: Apply input validation and sanitization for SQL queries.
• Long-term: Monitor MonetDB for official patches or updates. Consider migrating to a supported version if available.
• Workaround: Use application-level query filtering to block excessively long strings.

Valters IT