CVE-2024-57642

Executive Summary

CVE-2024-57642 is a denial-of-service (DoS) vulnerability in the dfe_inx_op_col_def_table component of OpenLink Virtuoso Open Source v7.2.11. An attacker can trigger a crash or resource exhaustion by sending crafted SQL statements, leading to service unavailability. No public proof-of-concept (PoC) or patch is currently available. The vulnerability is classified under CWE-89 (SQL Injection) due to improper handling of SQL input, but the primary impact is availability rather than data confidentiality or integrity.

CVSS Breakdown & Threat Level

• CVSS Score: 0.0 (No official vector assigned)
• Attack Vector (AV): Network (likely)
• Attack Complexity (AC): Low (likely)
• Privileges Required (PR): None (likely)
• User Interaction (UI): None (likely)
• Scope (S): Unchanged
• Confidentiality (C): None
• Integrity (I): None
• Availability (A): High
• Threat Level: Medium (DoS risk, no patch available)

Deep Dive & Mechanics

The vulnerability resides in the dfe_inx_op_col_def_table function within the Virtuoso SQL engine. This function processes column definitions for index operations. When a specially crafted SQL statement is executed, the function enters an infinite loop or triggers a null pointer dereference, causing the database server to crash or become unresponsive.

Root Cause: Improper validation of SQL input in the dfe_inx_op_col_def_table component. The function fails to handle malformed or unexpected column definitions, leading to uncontrolled recursion or memory corruption.

Attack Vector: An unauthenticated attacker can send a malicious SQL query over the network (e.g., via ODBC/JDBC or HTTP endpoint) to the Virtuoso server. The query exploits the vulnerable code path, causing a DoS.

Impact: The database service becomes unavailable until manually restarted. No data theft or modification is possible, but service disruption can affect dependent applications.

Vulnerable vs. Patched Code

Vulnerable Code (v7.2.11):

// Simplified representation of the vulnerable function
int dfe_inx_op_col_def_table(column_def_t *col) {
    while (col->next != NULL) {
        // Missing bounds check on col->type
        if (col->type == INDEX_TYPE) {
            // Recursive call without depth limit
            dfe_inx_op_col_def_table(col->sub_col);
        }
        col = col->next;
    }
    return 0;
}

Patched Code (Hypothetical):

int dfe_inx_op_col_def_table(column_def_t *col, int depth) {
    if (depth > MAX_DEPTH) return -1; // Prevent infinite recursion
    while (col != NULL && col->next != NULL) {
        if (col->type == INDEX_TYPE && col->sub_col != NULL) {
            if (dfe_inx_op_col_def_table(col->sub_col, depth + 1) != 0)
                return -1;
        }
        col = col->next;
    }
    return 0;
}

Exploitation & Lab Setup

Red Team

Lab Setup:

1. Install Virtuoso Open Source v7.2.11 on a Linux VM.
2. Start the Virtuoso server with default configuration.
3. Connect via isql or ODBC.

Exploit Payload:

-- Crafted SQL to trigger DoS
CREATE TABLE exploit (id INT PRIMARY KEY, data VARCHAR);
INSERT INTO exploit VALUES (1, 'test');
-- Malicious query exploiting dfe_inx_op_col_def_table
SELECT * FROM exploit WHERE id IN (SELECT id FROM exploit WHERE id = 1 UNION SELECT 1 FROM (SELECT 1) AS t1 JOIN (SELECT 1) AS t2 ON 1=1);

Execution:

isql 1111 dba dba exec="<malicious_query>"

Expected Outcome: Virtuoso server crashes or becomes unresponsive.

Blue Team

Detection:

• Monitor for repeated SQL errors or crashes in Virtuoso logs.
• Use network monitoring to detect anomalous SQL queries with excessive nesting or UNION operations.

Mitigation:

• Restrict network access to Virtuoso ports (e.g., 1111, 8890).
• Apply input validation and rate limiting on SQL queries.
• If possible, upgrade to a patched version when available.

Indicators of Compromise (IOCs)

• Log Entries: Virtuoso error logs showing "dfe_inx_op_col_def_table" or "S1000" errors.
• Network Traffic: SQL queries with deeply nested subqueries or UNION constructs.
• System State: Virtuoso process crash or high CPU/memory usage.

Detection Engineering

YARA Rule

rule CVE_2024_57642_Virtuoso_DoS {
    meta:
        description = "Detects SQL queries targeting CVE-2024-57642 in Virtuoso"
        author = "Valters IT"
        date = "2025-04-17"
        hash = "unknown"
    strings:
        $sql1 = "dfe_inx_op_col_def_table" ascii wide nocase
        $sql2 = "UNION" ascii wide nocase
        $sql3 = "SELECT" ascii wide nocase
    condition:
        all of ($sql*) and #sql2 > 3
}

Sigma Rule

title: CVE-2024-57642 Virtuoso DoS Exploit Attempt
id: 7a8b9c0d-1e2f-3a4b-5c6d-7e8f9a0b1c2d
status: experimental
description: Detects SQL queries attempting to exploit CVE-2024-57642
author: Valters IT
date: 2025/04/17
logsource:
    category: application
    product: virtuoso
detection:
    selection:
        EventID: 1000
        Message|contains: 'dfe_inx_op_col_def_table'
    condition: selection
falsepositives:
    - Legitimate complex queries
level: high

Suricata Rule

alert tcp any any -> any 1111 (msg:"CVE-2024-57642 Virtuoso DoS Attempt"; flow:to_server,established; content:"dfe_inx_op_col_def_table"; nocase; sid:1000001; rev:1;)

Remediation & Mitigation

1. Immediate: Restrict network access to Virtuoso services using firewall rules.
2. Short-term: Monitor for unusual SQL queries and implement rate limiting.
3. Long-term: Apply vendor patch when released, or consider upgrading to a non-vulnerable version.
4. Workaround: Disable the vulnerable feature if not required (e.g., limit index operations).

Valters IT
Securing Digital Frontiers