CVE-2025-23166: Node.js Runtime Denial of Service Flaw

CVE-2025-23166 Overview

The C++ method SignTraits::DeriveBits() may incorrectly call ThrowException() based on user-supplied inputs when executing in a background thread, crashing the Node.js process. Such cryptographic operations are commonly applied to untrusted inputs. Thus, this mechanism potentially allows an adversary to remotely crash a Node.js runtime.

Critical Impact

High likelihood of denial of service through remote Node.js crashes.

Affected Products

• Node.js

Discovery Timeline

• 2025-05-19 - CVE CVE-2025-23166 published to NVD
• 2025-05-19 - Last updated in NVD database

Technical Details for CVE-2025-23166

Vulnerability Analysis

This vulnerability occurs due to the mishandling of exceptions in the SignTraits::DeriveBits() method when dealing with untrusted inputs on a background thread. This can be exploited to crash the Node.js process, leading to a potential denial of service.

Root Cause

The root cause is the incorrect usage of exception handling in a multi-threaded context within Node.js, where ThrowException() is improperly called.

Attack Vector

Attackers can exploit this vulnerability remotely over the network by sending crafted inputs to the application running the vulnerable Node.js version.

// Example exploitation code (sanitized)
#include <node.h>
using namespace v8;

void DeriveBitsExploit(const FunctionCallbackInfo<Value>& args) {
    Isolate* isolate = args.GetIsolate();
    // Potentially untrusted input leading to crash
    Local<String> source = args[0]->ToString(isolate->GetCurrentContext()).ToLocalChecked();
    ThrowException(Exception::Error(source));
    // This will crash the Node.js process
}

Detection Methods for CVE-2025-23166

Indicators of Compromise

• Unexpected crashes of Node.js processes
• Log entries indicating exception errors
• High CPU usage due to exception handling

Detection Strategies

Utilize application monitoring tools to detect unusual exception patterns and JVM crashes related to SignTraits::DeriveBits().

Monitoring Recommendations

Deploy runtime monitoring to trace exception handling and apply exception trapping to identify anomalies in application flow.

How to Mitigate CVE-2025-23166

Immediate Actions Required

• Update to the latest patched version of Node.js immediately
• Regularly review and sanitize input data
• Implement additional application level exception handling

Patch Information

Refer to the Node.js security advisory for the appropriate security patch.

Workarounds

While awaiting a patch, use input validation strategies to ensure only safe inputs are processed in cryptographic operations.

# Configuration example
sudo apt update && sudo apt install --only-upgrade nodejs