CVE-2025-31990: HCL Velocity DoS Vulnerability

CVE-2025-31990 Overview

CVE-2025-31990 is a Denial of Service (DoS) vulnerability affecting HCL Velocity that stems from improper enforcement of rate limiting on certain API endpoints. This vulnerability allows attackers to flood the system with excessive requests, overwhelming server resources and rendering the application unresponsive to legitimate users. The vulnerability is classified under CWE-770 (Allocation of Resources Without Limits or Throttling).

Critical Impact

Successful exploitation could cause complete service disruption for HCL Velocity deployments, affecting DevOps pipeline operations and release management workflows.

Affected Products

• HCL Velocity versions prior to 5.1.7

Discovery Timeline

• 2026-02-07 - CVE CVE-2025-31990 published to NVD
• 2026-02-09 - Last updated in NVD database

Technical Details for CVE-2025-31990

Vulnerability Analysis

This vulnerability represents a resource exhaustion condition where the HCL Velocity application fails to properly enforce rate limiting mechanisms on specific API endpoints. Without proper throttling controls, the system cannot distinguish between normal operational traffic patterns and malicious request floods. The attack can be executed over the network and requires high privileges to exploit, though successful exploitation can have cross-scope impact on system availability.

The absence of rate limiting creates a direct path to resource exhaustion. When an attacker submits requests at a rate exceeding the server's processing capacity, system resources such as CPU, memory, network connections, and thread pools become saturated, ultimately causing legitimate requests to fail or timeout.

Root Cause

The root cause is improper implementation of resource allocation controls as classified by CWE-770 (Allocation of Resources Without Limits or Throttling). The affected API endpoints lack proper request throttling mechanisms, allowing unlimited request submission without enforcement of reasonable consumption boundaries. This design flaw enables attackers to consume disproportionate system resources through sustained high-volume requests.

Attack Vector

The attack vector is network-based, allowing remote exploitation without user interaction. An attacker with high-level privileges can target the unprotected API endpoints by sending a high volume of requests in rapid succession. The attack methodology involves:

1. Identifying API endpoints lacking rate limiting controls
2. Crafting automated request floods targeting these endpoints
3. Sustaining the attack to exhaust server resources
4. Maintaining the flood to prevent service recovery

The vulnerability mechanism exploits the absence of request throttling. When API calls are received, the server allocates resources to process each request without verifying whether the requester has exceeded reasonable usage thresholds. For detailed technical information, refer to the HCL Software Knowledge Base Article.

Detection Methods for CVE-2025-31990

Indicators of Compromise

• Abnormally high API request volumes from single source IPs or authenticated users
• Sudden spikes in server resource utilization (CPU, memory, network connections)
• Increased response latency or HTTP 503/504 error rates
• Application log entries showing repeated rapid-fire requests to the same endpoints

Detection Strategies

• Implement API gateway monitoring to track request rates per client/user
• Configure alerting thresholds for API call frequency anomalies
• Deploy network traffic analysis to identify request flood patterns
• Monitor HCL Velocity application logs for repeated authentication attempts followed by high-volume API calls

Monitoring Recommendations

• Establish baseline metrics for normal API usage patterns in your HCL Velocity deployment
• Configure real-time dashboards tracking requests per second, unique client counts, and error rates
• Set up automated alerts when request volumes exceed established thresholds
• Enable detailed API access logging for forensic analysis capabilities

How to Mitigate CVE-2025-31990

Immediate Actions Required

• Upgrade HCL Velocity to version 5.1.7 or later immediately
• Review current API access logs for signs of exploitation attempts
• Implement network-level rate limiting as a temporary compensating control
• Consider restricting API access to trusted networks or IP ranges until patch deployment

Patch Information

HCL has addressed this vulnerability in HCL Velocity version 5.1.7. Organizations should prioritize upgrading to this version or later to remediate the vulnerability. Additional details and patch download information are available in the HCL Software Knowledge Base Article.

Workarounds

• Deploy a Web Application Firewall (WAF) or API gateway with rate limiting capabilities in front of HCL Velocity
• Configure network-level connection throttling to limit requests per IP address
• Implement authentication-aware rate limiting at the load balancer level
• Temporarily restrict API access to essential operations and trusted clients only

# Example: Nginx rate limiting configuration as compensating control
# Add to nginx.conf or site configuration
limit_req_zone $binary_remote_addr zone=velocity_api:10m rate=10r/s;

location /api/ {
    limit_req zone=velocity_api burst=20 nodelay;
    limit_req_status 429;
    proxy_pass http://velocity_backend;
}