CVE-2024-53678 Overview
CVE-2024-53678 is a SQL injection vulnerability in Apache Virtual Computing Lab (VCL) affecting all versions from 2.2 through 2.5.1. The flaw resides in the Block Allocation request workflow, where authenticated users can tamper with submitted form data to alter a SELECT SQL statement executed by the application. The Apache VCL project has released version 2.5.2 to remediate the issue.
The vulnerability is classified under CWE-89: Improper Neutralization of Special Elements used in an SQL Command. Attackers cannot read the response of the injected SELECT statement directly, limiting immediate data exfiltration but leaving room for blind SQL injection techniques.
Critical Impact
Authenticated attackers can manipulate backend SQL SELECT queries through the Block Allocation request form, enabling blind SQL injection against the Apache VCL database.
Affected Products
- Apache VCL 2.2 through 2.5.1
- Apache VCL Block Allocation request functionality
- Deployments backed by MySQL/MariaDB databases used by Apache VCL
Discovery Timeline
- 2025-03-25 - CVE-2024-53678 published to NVD
- 2026-06-17 - Last updated in NVD database
Technical Details for CVE-2024-53678
Vulnerability Analysis
Apache VCL provides remote access to dedicated compute environments for classroom and lab use. The Block Allocation feature lets privileged users reserve pools of resources for scheduled sessions. When a Block Allocation request is submitted, form parameters flow into a SELECT query without sufficient neutralization of SQL metacharacters.
An authenticated user with the required privileges can modify request fields so that the resulting SELECT statement is restructured. The injected query executes under the database context used by Apache VCL. Because the response body does not return the query results, exploitation follows a blind SQL injection pattern using boolean or time-based inference.
The scope of the vulnerability is limited to SELECT operations reachable from the Block Allocation code path. However, blind extraction can expose credentials, session data, and configuration stored in the VCL schema.
Root Cause
The root cause is improper neutralization of user-supplied input concatenated into a SQL statement. The Block Allocation handler does not use parameterized queries or strict input validation for all fields, allowing SQL metacharacters to alter query semantics.
Attack Vector
Exploitation requires network access to the Apache VCL web interface and valid credentials with permission to submit Block Allocation requests. The attacker intercepts or replays the form submission and injects SQL syntax into a vulnerable parameter. Since the response does not echo query output, the attacker uses blind inference techniques such as conditional delays or boolean discrimination to extract data.
Refer to the Apache Security Mailing List advisory and the OpenWall OSS-Security discussion for technical details published by the project.
Detection Methods for CVE-2024-53678
Indicators of Compromise
- Block Allocation form submissions containing SQL metacharacters such as single quotes, UNION, SLEEP(, BENCHMARK(, or comment sequences like -- and /*.
- Unusually long response times on Block Allocation endpoints, indicating time-based blind SQL injection probes.
- Database logs showing malformed or unexpected SELECT statements originating from the VCL application user.
Detection Strategies
- Enable query logging on the MySQL/MariaDB backend and alert on SELECT statements from the VCL service account that reference system tables or use inference functions.
- Deploy a web application firewall (WAF) with SQL injection signatures in front of the Apache VCL frontend and log matches to Block Allocation URLs.
- Correlate authenticated session activity with anomalous POST payloads on Block Allocation request handlers.
Monitoring Recommendations
- Continuously monitor authenticated user sessions submitting Block Allocation requests for high-volume or repeated failed attempts.
- Baseline normal Block Allocation request timing and alert on statistically significant latency deviations.
- Forward Apache VCL and database logs to a centralized analytics platform for cross-correlation and retention.
How to Mitigate CVE-2024-53678
Immediate Actions Required
- Upgrade Apache VCL to version 2.5.2, which contains the official fix for CVE-2024-53678.
- Audit accounts with permission to submit Block Allocation requests and remove privileges that are not required.
- Review database and web server logs for prior evidence of SQL injection attempts against Block Allocation endpoints.
Patch Information
The Apache VCL project addressed CVE-2024-53678 in version 2.5.2. Administrators should follow the upgrade guidance published on the Apache Security Mailing List. All versions from 2.2 through 2.5.1 remain vulnerable and should not be run in production.
Workarounds
- Restrict access to the Apache VCL management interface to trusted networks using firewall or VPN controls until the upgrade is applied.
- Reduce the number of accounts that can submit Block Allocation requests to the minimum necessary set.
- Place a WAF in front of Apache VCL with rules that block SQL injection patterns in Block Allocation form fields.
# Example: restrict access to VCL management endpoints with iptables
iptables -A INPUT -p tcp --dport 443 -s 10.0.0.0/24 -j ACCEPT
iptables -A INPUT -p tcp --dport 443 -j DROP
Disclaimer: This content was generated using AI. While we strive for accuracy, please verify critical information with official sources.
