CVE-2020-36950: Laravel Nova 3.7.0 DOS Vulnerability

CVE-2020-36950 Overview

CVE-2020-36950 is a denial of service (DoS) vulnerability affecting Laravel Nova version 3.7.0. This vulnerability allows authenticated users to crash the application by manipulating the range parameter in requests. By sending simultaneous requests with an extremely high range value, attackers can overwhelm server resources and cause the application to become unresponsive or crash entirely.

Critical Impact

Authenticated attackers can exploit this vulnerability to cause complete service disruption by exhausting server resources through malicious range parameter manipulation.

Affected Products

• Laravel Nova 3.7.0

Discovery Timeline

• 2026-01-27 - CVE-2020-36950 published to NVD
• 2026-01-29 - Last updated in NVD database

Technical Details for CVE-2020-36950

Vulnerability Analysis

This denial of service vulnerability stems from improper resource allocation when processing the range parameter in Laravel Nova 3.7.0. The application fails to properly validate or limit the range values submitted by authenticated users, allowing attackers to specify arbitrarily large values that consume excessive server resources.

The vulnerability is classified under CWE-770 (Allocation of Resources Without Limits or Throttling), indicating that the application does not implement adequate controls to prevent resource exhaustion. When an authenticated user submits requests with extremely high range values, the server attempts to process these requests without proper bounds checking, leading to memory exhaustion or CPU overload.

The attack can be amplified by sending multiple simultaneous requests, each containing malicious range parameters. This concurrent exploitation approach accelerates resource depletion and can quickly render the application unavailable to legitimate users.

Root Cause

The root cause of CVE-2020-36950 is the absence of input validation and resource allocation limits for the range parameter within Laravel Nova 3.7.0. The application accepts user-supplied range values without implementing maximum thresholds or rate limiting mechanisms. This design flaw allows authenticated users to abuse the functionality by submitting values that exceed reasonable operational bounds, triggering excessive memory allocation or computational operations that exhaust available server resources.

Attack Vector

The attack is executed over the network by authenticated users who have access to Laravel Nova's administrative interface. The exploitation process involves:

1. An authenticated attacker identifies endpoints that accept the range parameter
2. The attacker crafts requests containing extremely large range values
3. Multiple simultaneous requests are sent to the vulnerable endpoint
4. The server attempts to process these requests, allocating resources for each
5. Server resources become exhausted, causing application instability or complete unavailability

For detailed technical information about the exploitation technique, refer to the Exploit-DB #49198 entry and the VulnCheck Laravel Nova Advisory.

Detection Methods for CVE-2020-36950

Indicators of Compromise

• Unusual spikes in HTTP requests containing the range parameter with abnormally large values
• Server resource utilization (CPU, memory) spiking to near-maximum levels without corresponding legitimate user activity
• Application logs showing repeated requests from the same authenticated user targeting range-related endpoints
• Service interruptions or application crashes coinciding with patterns of suspicious range parameter usage

Detection Strategies

• Implement Web Application Firewall (WAF) rules to flag or block requests containing range parameter values exceeding normal operational thresholds
• Configure application-level logging to capture and alert on requests with abnormally large range parameters
• Deploy anomaly detection systems to identify patterns of concurrent requests from single users targeting the same endpoints
• Monitor authentication logs for users exhibiting unusual request patterns that could indicate exploitation attempts

Monitoring Recommendations

• Set up real-time alerting for server resource utilization exceeding defined thresholds
• Implement request rate monitoring for authenticated users to detect burst patterns indicative of DoS attempts
• Configure application performance monitoring (APM) tools to track response times and identify degradation patterns
• Review access logs regularly for authenticated users making excessive requests with manipulated parameters

How to Mitigate CVE-2020-36950

Immediate Actions Required

• Upgrade Laravel Nova to a version that addresses this vulnerability by implementing proper input validation for the range parameter
• Implement server-side validation to enforce maximum allowable values for the range parameter
• Configure rate limiting for authenticated users to prevent request flooding
• Review and restrict access to Laravel Nova administration to only essential personnel

Patch Information

Users should upgrade Laravel Nova to the latest available version that includes fixes for this vulnerability. Consult the Laravel Nova Release Notes for information about patched versions and upgrade instructions. The official Laravel Nova Homepage provides documentation and support resources for the upgrade process.

Workarounds

• Implement middleware to validate and cap the range parameter value at a reasonable maximum threshold before processing
• Configure web server or reverse proxy (e.g., Nginx, Apache) to limit request body size and parameter values
• Deploy rate limiting at the application or infrastructure level to restrict the number of requests per user within a given time window
• Consider implementing request queuing to prevent simultaneous processing of resource-intensive operations

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

server {
    location /nova {
        limit_req zone=nova_limit burst=20 nodelay;
        # Additional Nova location configuration
    }
}