Open-source alternatives to Verifyfetch

Endo is a distributed secure JavaScript sandbox, based on SES

JSON.parse() drop-in replacement with prototype poisoning protection

Checks all maintainers of all NPM and Pypi packages for hijackable packages through domain re-registration

An incremental cache for the web

sw-precache is a service worker precache generator used to create scripts that enable offline functionality for web applications. It acts as a build-time asset cache manager that hashes static files and manages their versioning within a service worker cache. The project provides a runtime cache configurator to define caching strategies and request handlers for dynamic content based on URL patterns. It also includes an offline fallback handler to intercept network failures and serve cached fallback pages. The toolset covers the generation of service worker code and manifests, content-hash bas

Service Worker Toolbox provides some simple helpers for use in creating your own service workers. Specifically, it provides common caching strategies for dynamic content, such as API calls, third-party resources, and large or infrequently used local resources that you don't want precached.

Workbox is a modular library and toolkit designed for managing service workers in progressive web applications. It provides a comprehensive framework for handling asset caching, request routing, and background script lifecycle management, enabling developers to build web applications that function reliably offline and load efficiently. The project distinguishes itself through a declarative routing engine and a plugin-based architecture that allows for the injection of custom logic into the request and response processing pipeline. It supports advanced caching patterns, such as cache-first or

This project is a comprehensive repository of curated domain blocklists designed for network-wide DNS filtering. It functions as a DNS sinkhole feed, providing the necessary data to intercept and block unwanted network requests at the resolution layer before they reach their destination. By returning null or loopback addresses for identified domains, it prevents connections to malicious infrastructure, advertising servers, and tracking endpoints across all devices on a network. The repository distinguishes itself through a tiered categorization logic that allows users to select protection lev

JSON.parse() drop-in replacement with prototype poisoning protection

tools for sandboxing your dependency graph

js-xss is an HTML XSS sanitizer and whitelist-based HTML filter designed to remove malicious code from untrusted HTML. It serves as a tool for cross-site scripting prevention and user-generated content management by cleaning HTML strings to ensure safe browser rendering. The library includes a CSS style validator to scrub inline styles against a whitelist and an HTML content purifier capable of stripping all tags to extract raw text. It allows for custom HTML filtering through the definition of specific rules and handler functions to control permitted elements and attributes. The tool covers

Detect Glassworm & trojan source attacks that employ unicode bidi attacks to inject malicious code

package that checks if your Node.js installation is vulnerable to known security vulnerabilities

The authentication CLI & Proxy for AI agents. Give agents access, not your credentials.

Tiny helper to protect against Prototype Pollution vulnerabilities in your application regardless if they introduced in your own code or in 3rd-party code

Mitigate security concerns of Dependency Confusion supply chain security risks

UpUp is a service worker framework and progressive web app tool designed to provide websites with offline capabilities. It functions as a browser cache manager that enables offline website availability by utilizing service workers and the cache API. The project manages the offline workflow through static asset pre-caching and version-based cache busting to ensure stored resources remain current. It also includes offline fallback management to define specific pages or content that display to users when a network connection is unavailable and the requested resource is not cached. Additional ca

Tor detect middleware for express

Brute-force protection middleware for express routes by rate limiting incoming requests

Open-source, invisible CAPTCHA that detects AI agents, bots, and headless browsers via 40+ behavioral signals, device & TLS fingerprinting, and SHA-256 proof of work. Self-hosted and privacy-first.

Database security suite. Database proxy with field-level encryption, search through encrypted data, SQL injections prevention, intrusion detection, honeypots. Supports client-side and proxy-side ("transparent") encryption. SQL, NoSQL.

DOMPurify is a security-focused library designed to sanitize untrusted HTML input, preventing cross-site scripting attacks by stripping malicious code while preserving safe content. It functions as a utility for secure document object model manipulation, ensuring that user-provided rich text can be rendered safely within web applications. The library distinguishes itself through a single-pass, mutation-observer-free processing model that operates on detached document fragments to avoid triggering unintended side effects. It employs recursive node traversal and context-aware logic to inspect a