CVE-2024-57625

Executive Summary

CVE-2024-57625 is a denial-of-service (DoS) vulnerability in the MonetDB Server v11.49.1, specifically within the merge_table_prune_and_unionize component. An attacker can exploit this by sending crafted SQL statements, causing the server to crash or become unresponsive. The vulnerability has a CVSS score of 0.0 (likely unassigned or placeholder), and no public exploit or patch is currently available. The EPSS score is 0.0%, indicating low exploitation activity in the wild.

Supply Chain & Package Security

MonetDB is an open-source column-oriented database management system. This vulnerability affects the core server binary, not a package manager distribution (NPM, PyPI, Go, Ruby). Therefore, supply chain risks are limited to the direct deployment of the MonetDB server.

CVSS Breakdown & Threat Level

• CVSS Score: 0.0 (Unassigned)
• Attack Vector: Network (likely)
• Attack Complexity: Low (crafted SQL statements)
• Privileges Required: None (unauthenticated SQL injection possible)
• User Interaction: None
• Scope: Unchanged
• Confidentiality Impact: None
• Integrity Impact: None
• Availability Impact: High (DoS)
• Threat Level: Medium (due to DoS impact and lack of patch)

Deep Dive & Mechanics

The vulnerability resides in the merge_table_prune_and_unionize function within MonetDB's SQL optimizer. This function is responsible for optimizing queries involving merge tables (a type of partitioned table). When a specially crafted SQL statement is processed, the function enters an infinite loop or triggers a segmentation fault due to improper input validation or memory management. The exact mechanism involves recursive pruning and unionization logic that fails to handle certain edge cases, leading to resource exhaustion or crash.

Vulnerable vs. Patched Code

Vulnerable Code (v11.49.1): The merge_table_prune_and_unionize function lacks bounds checking on the number of partitions or union branches. An attacker can craft a query that causes an exponential explosion in the number of union operations.

// Simplified vulnerable pseudocode
void merge_table_prune_and_unionize(MergeTable *mt) {
    for (int i = 0; i < mt->num_partitions; i++) {
        // No check for recursion depth or partition count
        merge_table_prune_and_unionize(mt->partitions[i]);
    }
}

Patched Code (hypothetical): A patch would add recursion depth limits and partition count validation.

// Patched version
void merge_table_prune_and_unionize(MergeTable *mt, int depth) {
    if (depth > MAX_DEPTH) return; // Prevent infinite recursion
    if (mt->num_partitions > MAX_PARTITIONS) return; // Limit partitions
    for (int i = 0; i < mt->num_partitions; i++) {
        merge_table_prune_and_unionize(mt->partitions[i], depth + 1);
    }
}

Exploitation & Lab Setup

Red Team

Lab Setup:

1. Install MonetDB v11.49.1 on a Linux VM.
2. Create a merge table with multiple partitions.
3. Execute the following crafted SQL to trigger the DoS:

-- Crafted query to cause infinite recursion
SELECT * FROM merge_table WHERE 1=1 UNION ALL SELECT * FROM merge_table WHERE 1=1 UNION ALL ... (repeat many times)

Exploit Code: No public exploit code is available. The above SQL statement is a conceptual example.

Blue Team

Detection:

• Monitor for excessive SQL queries with many UNION ALL clauses.
• Monitor for high CPU/memory usage on the MonetDB server.
• Use the Sigma rule below to detect anomalous query patterns.

Indicators of Compromise (IOCs)

• Network: Unusual SQL queries with excessive UNION ALL or nested subqueries.
• System: MonetDB server crash logs containing merge_table_prune_and_unionize in the stack trace.
• File: Core dump files in /var/log/monetdb/ or similar.

Detection Engineering

YARA Rule

rule CVE_2024_57625_MonetDB_DoS {
    meta:
        description = "Detects MonetDB crash logs related to CVE-2024-57625"
        author = "Valters IT"
        date = "2025-04-10"
    strings:
        $s1 = "merge_table_prune_and_unionize" ascii nocase
        $s2 = "segmentation fault" ascii nocase
        $s3 = "Assertion" ascii nocase
    condition:
        any of ($s1) and any of ($s2, $s3)
}

Sigma Rule

title: MonetDB DoS via Crafted SQL (CVE-2024-57625)
id: 12345678-1234-1234-1234-123456789abc
status: experimental
description: Detects SQL queries with excessive UNION ALL clauses targeting MonetDB
logsource:
    category: application
    product: monetdb
detection:
    selection:
        query|contains: "UNION ALL"
    condition: selection and count(query) > 100
falsepositives:
    - Legitimate complex queries
level: high

Suricata Rule

alert tcp any any -> any 50000 (msg:"CVE-2024-57625 MonetDB DoS Attempt"; flow:to_server,established; content:"UNION ALL"; threshold:type both, track by_src, count 50, seconds 60; classtype:attempted-dos; sid:1000001; rev:1;)

Remediation & Mitigation

• Immediate: Restrict network access to the MonetDB server (firewall rules). Use a WAF to filter SQL queries with excessive UNION ALL.
• Short-term: Monitor for patches from MonetDB. Apply input validation on SQL queries at the application layer.
• Long-term: Upgrade to a patched version once available. Implement query complexity limits in the database configuration.

Valters IT
DevSecOps & Cyber Threat Intelligence