Browse free open source Security software and projects for Windows and Linux below. Use the toggles on the left to filter open source Security software by OS, license, language, programming language, and project status.

  • Fully Managed MySQL, PostgreSQL, and SQL Server Icon
    Fully Managed MySQL, PostgreSQL, and SQL Server

    Automatic backups, patching, replication, and failover. Focus on your app, not your database.

    Cloud SQL handles your database ops end to end, so you can focus on your app.
    Try Free
  • Try Google Cloud Risk-Free With $300 in Credit Icon
    Try Google Cloud Risk-Free With $300 in Credit

    No hidden charges. No surprise bills. Cancel anytime.

    Use your credit across every product. Compute, storage, AI, analytics. When it runs out, 20+ products stay free. You only pay when you choose to.
    Start Free
  • 1
    KeePass

    KeePass

    A lightweight and easy-to-use password manager

    KeePass Password Safe is a free, open source, lightweight, and easy-to-use password manager for Windows, Linux and Mac OS X, with ports for Android, iPhone/iPad and other mobile devices. With so many passwords to remember and the need to vary passwords to protect your valuable data, it’s nice to have KeePass to manage your passwords in a secure way. KeePass puts all your passwords in a highly encrypted database and locks them with one master key or a key file. As a result, you only have to remember one single master password or select the key file to unlock the whole database. And the databases are encrypted using the best and most secure encryption algorithms currently known, AES and Twofish. See our features page for details.
    Leader badge
    Downloads: 330,153 This Week
    Last Update:
    See Project
  • 2
    Anti-Spam SMTP Proxy Server

    Anti-Spam SMTP Proxy Server

    Anti-Spam SMTP Proxy Server implements multiple spam filters

    The Anti-Spam SMTP Proxy (ASSP) Server project aims to create an open source platform-independent SMTP Proxy server which implements auto-whitelists, self learning Hidden-Markov-Model and/or Bayesian, Greylisting, DNSBL, DNSWL, URIBL, SPF, SRS, Backscatter, Virus scanning, attachment blocking, Senderbase and multiple other filter methods. Click 'Files' to download the professional version 2.8.1 build 24261. A linux(ubuntu 20.04 LTS) and a freeBSD 12.2 based ready to run OVA of ASSP V2 are also available for download. NOTICE: V1 development has been stopped at the end of 2014 (1.10.1 build 16060). Possibly there will be done some bugfixing in future. Please upgrade to V2, which is and will be actively maintained.
    Leader badge
    Downloads: 50,433 This Week
    Last Update:
    See Project
  • 3
    Tor Browser

    Tor Browser

    Browser for using Tor on Windows, Mac OS X or Linux

    Tor Browser enables you to use Tor on Windows, Mac OS X, or Linux without needing to install any software. Tor is a software that bounces your communications around a distributed network of relays run by volunteers. This effectively prevents anyone watching your Internet connection from learning what sites you visit; it prevents the sites you visit from learning your physical location; and allows you access to sites which are blocked. Tor Browser can run off a USB flash drive, comes with a pre-configured web browser to protect your anonymity, and is self-contained (portable).
    Downloads: 891 This Week
    Last Update:
    See Project
  • 4
    Angry IP Scanner

    Angry IP Scanner

    A cross-platform network scanner that is fast and simple to use

    Angry IP scanner is fast and friendly network scanner for Windows, Linux, and Mac. It is very extensible, allowing it to be used for very wide range of purposes, with the primary goal of being useful to network administrators.
    Leader badge
    Downloads: 2,316 This Week
    Last Update:
    See Project
  • Full-stack observability with actually useful AI | Grafana Cloud Icon
    Full-stack observability with actually useful AI | Grafana Cloud

    Our generous forever free tier includes the full platform, including the AI Assistant, for 3 users with 10k metrics, 50GB logs, and 50GB traces.

    Built on open standards like Prometheus and OpenTelemetry, Grafana Cloud includes Kubernetes Monitoring, Application Observability, Incident Response, plus the AI-powered Grafana Assistant. Get started with our generous free tier today.
    Create free account
  • 5
    SoftEther VPN

    SoftEther VPN

    Cross-platform multi-protocol VPN software

    An open-source free cross-platform multi-protocol VPN program, as an academic project from University of Tsukuba, under the Apache License 2.0. The API Suite allows you to easily develop your original SoftEther VPN Server management application to control the VPN Server (e.g. creating users, adding Virtual Hubs, disconnecting a specified VPN sessions) from JavaScript, TypeScript, C# or other languages. SoftEther VPN ("SoftEther" means "Software Ethernet") is one of the world's most powerful and easy-to-use multi-protocol VPN software. It runs on Windows, Linux, Mac, FreeBSD and Solaris. SoftEther VPN is an optimum alternative to OpenVPN and Microsoft's VPN servers. SoftEther VPN has a clone-function of OpenVPN Server. You can integrate from OpenVPN to SoftEther VPN smoothly. SoftEther VPN is faster than OpenVPN. SoftEther VPN also supports Microsoft SSTP VPN for Windows Vista / 7 / 8. No more need to pay expensive charges for Windows Server license for Remote-Access VPN function.
    Downloads: 126 This Week
    Last Update:
    See Project
  • 6
    AWStats

    AWStats

    AWStats Log Analyzer

    AWStats is a free powerful and featureful server logfile analyzer that shows you all your Web/Mail/FTP statistics including visits, unique visitors, pages, hits, rush hours, os, browsers, search engines, keywords, robots visits, broken links and more
    Leader badge
    Downloads: 304 This Week
    Last Update:
    See Project
  • 7
    Mullvad VPN desktop and mobile app

    Mullvad VPN desktop and mobile app

    The Mullvad VPN client app for desktop and mobile

    In a society that is increasingly determined to weaken that right, a fast, reliable and easy-to-use VPN connection is a good first step towards achieving this. By connecting to the Internet with Mullvad, we ensure that traffic to and from your device is encrypted to the highest standards, even when using public Wi-Fi in a coffee shop or hotel. We do not keep activity logs or ask for personal information, and we even encourage anonymous payments using cash or any of the accepted cryptocurrencies. Your IP address will be replaced with one of ours, ensuring that device activity and location are not linked to your user. Using Mullvad is quick and easy - just download and install the app. Don't spend time on complicated setup and multi-step registration processes. We designed Mullvad to be easy to use. Privacy is essential in a well-functioning society, as it allows norms, ethics and laws to be safely debated and challenged. Without privacy, a free and open society cannot flourish or exist.
    Downloads: 61 This Week
    Last Update:
    See Project
  • 8
    theHarvester

    theHarvester

    E-mails, subdomains and names

    theHarvester is a very simple to use, yet powerful and effective tool designed to be used in the early stages of a penetration test or red team engagement. Use it for open source intelligence (OSINT) gathering to help determine a company's external threat landscape on the internet. The tool gathers emails, names, subdomains, IPs and URLs using multiple public data sources.
    Downloads: 47 This Week
    Last Update:
    See Project
  • 9
    mod_qos

    mod_qos

    Quality of service module for Apache httpd

    mod_qos is a quality of service module for the Apache Web Server. It implements control mechanisms that can provide different priority to different requests and controls server access based on available resources.
    Leader badge
    Downloads: 1,210 This Week
    Last Update:
    See Project
  • Earn up to 16% annual interest with Nexo. Icon
    Earn up to 16% annual interest with Nexo.

    More flexibility. More control.

    Generate interest, access liquidity without selling, and execute trades seamlessly. All in one platform. Geographic restrictions, eligibility, and terms apply.
    Get started with Nexo.
  • 10
    Buster

    Buster

    Captcha solver extension for humans

    Save time by asking Buster to solve captchas for you. Buster is a Firefox extension which helps you to solve difficult captchas by completing reCAPTCHA audio challenges using speech recognition. Challenges are solved by clicking on the extension button at the bottom of the reCAPTCHA widget. It is not guaranteed that challenges are always solved, the limitations of the technology need to be considered. The continued development of Buster is made possible thanks to the support of awesome backers. If you'd like to join them, please consider contributing with Patreon, PayPal or Bitcoin. The success rate of the extension can be improved by simulating user interactions with the help of a client app. Follow the instructions from the extension's options to download and install the client app on Windows, Linux and macOS, or get the app from this repository.
    Downloads: 42 This Week
    Last Update:
    See Project
  • 11
    FlareSolverr

    FlareSolverr

    Proxy server to bypass Cloudflare protection

    FlareSolverr is a proxy server to bypass Cloudflare and DDoS-GUARD protection. FlareSolverr starts a proxy server, and it waits for user requests in an idle state using few resources. When some request arrives, it uses puppeteer with the stealth plugin to create a headless browser (Firefox). It opens the URL with user parameters and waits until the Cloudflare challenge is solved (or timeout). The HTML code and the cookies are sent back to the user, and those cookies can be used to bypass Cloudflare using other HTTP clients. Web browsers consume a lot of memory. If you are running FlareSolverr on a machine with few RAM, do not make many requests at once. With each request, a new browser is launched. It is also possible to use a permanent session. However, if you use sessions, you should make sure to close them as soon as you are done using them. It is recommended to install using a Docker container because the project depends on an external browser that is already included.
    Downloads: 40 This Week
    Last Update:
    See Project
  • 12
    Gobuster

    Gobuster

    Directory/File, DNS and VHost busting tool written in Go

    Gobuster is a tool used to brute-force. This project is born out of the necessity to have something that didn't have a fat Java GUI (console FTW), something that did not do recursive brute force, something that allowed me to brute force folders and multiple extensions at once, something that compiled to native on multiple platforms, something that was faster than an interpreted script (such as Python), and something that didn't require a runtime. Provides several modes, like the classic directory brute-forcing mode, DNS subdomain brute-forcing mode, the mode that enumerates open S3 buckets and looks for existence and bucket listings, and the virtual host brute-forcing mode (not the same as DNS!). Since this tool is written in Go you need to install the Go language/compiler/etc. Full details of installation and set up can be found on the Go language website. Once installed you have two options. You need at least go 1.16.0 to compile gobuster.
    Downloads: 39 This Week
    Last Update:
    See Project
  • 13
    gost

    gost

    GO Simple Tunnel, a simple tunnel written in golang

    A simple security tunnel written in Golang. Listening on multiple ports, multi-level forward proxies - proxy chain, standard HTTP/HTTPS/HTTP2/SOCKS4(A)/SOCKS5 proxy protocols support. Probing resistance support for web proxy, TLS encryption via negotiation support for SOCKS5 proxy. Support multiple tunnel types, tunnel UDP over TCP. Local/remote TCP/UDP port forwarding, TCP/UDP Transparent proxy, Shadowsocks Protocol (TCP/UDP), and SNI Proxy. Permission control, load balancing, route control, DNS resolver and proxy, and TUN/TAP Device. In GOST, GOST and other proxy services are considered as proxy nodes, GOST can handle the requests itself, or forward the requests to any one or more proxy nodes. In addition to configuring services directly from the command line, parameters can also be set by specifying the external configuration file with the -C parameter.
    Downloads: 34 This Week
    Last Update:
    See Project
  • 14
    Adguard Browser Extension

    Adguard Browser Extension

    AdGuard browser extension

    AdGuard is a fast and lightweight ad-blocking browser extension that effectively blocks all types of ads and trackers. AdGuard is a fast and lightweight ad blocking browser extension that effectively blocks all types of ads and trackers on all web pages. We focus on advanced privacy protection features to not just block known trackers, but prevent web sites from building your shadow profile. Unlike its standalone counterparts (AG for Windows, Mac), the browser extension is completely free and open source. You can learn more about the difference here. AdGuard does not collect any information about you, and does not participate in any acceptable ads program. The only source of income we have is selling premium versions of our software, and we intend to keep it that way. AdGuard for Windows is not just another ad blocker, it is a multipurpose tool that combines all necessary features for the best web experience. It blocks ads and dangerous websites, speeds up page loading, etc.
    Downloads: 29 This Week
    Last Update:
    See Project
  • 15
    Tamper Dev

    Tamper Dev

    Extension that allows you to intercept and edit HTTP/HTTPS requests

    If you are a developer, you can use Tamper Dev to debug your websites, or if you are a pentester, you can use it to search for security vulnerabilities by inspecting the HTTP traffic from your browser. Unlike most other extensions, Tamper Dev allows you to intercept, inspect and modify the requests before they are sent to the server. This extension provides functionality similar to Burp Proxy, MITM Proxy, OWASP ZAP, Tamper Data, and Postman Proxy, but without the need of additional software, with full support of HTTPS connections, and trivial to set-up (just install).
    Downloads: 29 This Week
    Last Update:
    See Project
  • 16
    Pomerium

    Pomerium

    Pomerium is an identity and context-aware access proxy

    Secure, context-aware access that just works. Access internal resources securely. Implement zero trust. Achieve compliance. All without the headache of a VPN. For teams that prefer a hosted solution while keeping data governance. For organizations that need advanced scaling, access control, and governance capabilities. IT and developers need a scalable access control solution to keep users productive, happy, and secure. Pomerium uses identity and context to ensure secure access to internal applications, servers, and infrastructure even from untrusted networks. Pomerium adds authentication and authorization to any application or server, giving IT Management a centralized panel for organization-wide control. Assert compliance in your current architecture without giving up control over data tenancy. Pomerium supports your infrastructure and can be deployed in all environments: cloud, hybrid, or on-prem. From AWS to Kubernetes and more, your internal and 3rd-party apps are covered.
    Downloads: 27 This Week
    Last Update:
    See Project
  • 17
    Algo VPN

    Algo VPN

    Set of Ansible scripts that simplifies the setup of a personal VPN

    Introducing Algo, a self-hosted personal VPN server designed for ease of deployment and security. Algo automatically deploys an on-demand VPN service in the cloud that is not shared with other users, relies on only modern protocols and ciphers, and includes only the minimal software you need. And it’s free. For anyone who is privacy conscious, travels for work frequently, or can’t afford a dedicated IT department, this one’s for you. Really, the paid-for services are just commercial honeypots. If an attacker can compromise a VPN provider, they can monitor a whole lot of sensitive data. Paid-for VPNs tend to be insecure: they share keys, their weak cryptography gives a false sense of security, and they require you to trust their operators. Even if you’re not doing anything wrong, you could be sharing the same endpoint with someone who is. In that case, your network traffic will be analyzed when law enforcement makes that seizure.
    Downloads: 26 This Week
    Last Update:
    See Project
  • 18
    Udp2raw-tunnel

    Udp2raw-tunnel

    Turns UDP traffic into encrypted UDP/fakeTCP/ICMP traffic

    A tunnel which turns UDP traffic into encrypted fakeTCP/UDP/ICMP traffic by using Raw Socket, helps you bypass UDP FireWalls(or unstable UDP environment). When used alone, Udp2raw tunnels only UDP traffic. Nevertheless, if you used udp2raw + any UDP-based VPN together, you can tunnel any traffic(include TCP/UDP/ICMP), currently, OpenVPN/L2TP/ShadowVPN and tinyfecVPN are confirmed to be supported. Linux host (including desktop Linux,Android phone/tablet,OpenWRT router,or Raspberry PI) with root account or cap_net_raw capability. ICMP/FakeTCP headers help you bypass UDP blocking, UDP QOS or improper UDP NAT behavior on some ISPs. In ICMP header mode,udp2raw works like an ICMP tunnel. UDP headers are also supported. In UDP header mode, it behaves just like a normal UDP tunnel, and you can just make use of the other features (such as encryption, anti-replay, or connection stalization).
    Downloads: 21 This Week
    Last Update:
    See Project
  • 19
    A KeePass plugin that downloads and stores favicons. A favicon is the little icon / logo used to identify many websites, typically displayed in the browser's address bar, bookmark list and on tabs.
    Leader badge
    Downloads: 95 This Week
    Last Update:
    See Project
  • 20
    Cryptomator

    Cryptomator

    Multi-platform transparent client-side encryption for your cloud files

    Cryptomator is a free and open source project that offers multi-platform, transparent client side encryption of your files in the cloud. It works with just about any cloud storage service; is totally transparent so you can work with your files how you normally would; and secure with a 256-bit key length AES encryption. It’s also simple and easy to use with no need for different accounts, key management, cloud access grants or cipher configurations.
    Downloads: 17 This Week
    Last Update:
    See Project
  • 21
    AlienVault OSSIM

    AlienVault OSSIM

    Open Source SIEM

    OSSIM, AlienVault’s Open Source Security Information and Event Management (SIEM) product, provides event collection, normalization and correlation. For more advanced functionality, AlienVault Unified Security Management (USM) builds on OSSIM with these additional capabilities: * Log management * Advanced threat detection with a continuously updated library of pre-built correlation rules * Actionable threat intelligence updates from AlienVault Labs Security Research Team * Rich analytics dashboards and data visualization
    Leader badge
    Downloads: 106 This Week
    Last Update:
    See Project
  • 22
    OpenAS2

    OpenAS2

    AS2 1.1 server implementation in Java

    OpenAS2 is a java-based implementation of the EDIINT AS2 standard. It is intended to be used as a server. It is extremely configurable and supports a wide variety of signing and encryption algorithms. Supports very high traffic volume allowing parallel processing of files per partner. SUPPORT: Please use the Github issues and Discussions channels here: https://github.com/OpenAS2/OpenAs2App/ Requirements: - Java 11 or newer (tested with the LTS versions of Java up to 21) - Any OS that runs Java Planned enhancements in the next major release: - User interace configuration GUI - Certificate Exchange Management IMPORTANT: Java 8 is no longer supported.
    Leader badge
    Downloads: 80 This Week
    Last Update:
    See Project
  • 23
    Sn3rpOs_v7.21: CoNt4g1N

    Sn3rpOs_v7.21: CoNt4g1N

    TinFoilSec Presents: Sn3rpOs_v7.21 (CoNt4g1N)

    *Updated 11/05/2021 TinfoilSec Presents: Sn3rpOs [Codename: CoNt4g1N] Features: Xfce4 Desktop Kali Linux Full System Torified with Privoxy & Tor bleachbit Wire Signal Veracrypt All repos transported through Privoxy&Tor dnscrypt-proxy (no-logs) Tor Browser Custom Tor Switcher and Pyloris Firefox-esr (configured with tor) Thunderbird ProtonVPN (Free VPN no-logs) Sn1per Vault Scanner RED_HAWK Fork of Kali Rolling, Debian Stretch/Buster -No Back Doors- Now with UEFI boot support and of course bacon. XD login: tfs passwd: toor As Always RTFM! (README file)
    Downloads: 77 This Week
    Last Update:
    See Project
  • 24
    Bitwarden Browser Extension

    Bitwarden Browser Extension

    The Bitwarden browser extension vault

    Bitwarden Browser Extension lets you integrate Bitwarden directly into your browser of choice. Bitwarden is an open source password management solution that stores all your sensitive information securely in an encrypted vault. With this extension, you will be able to easily and conveniently access Bitwarden through your browser. Bitwarden Browser Extension is written using the Web Extension API and Angular, and supports a variety of browsers. These include Chrome, Firefox, Opera, Edge, Safari and many other popularly used browsers.
    Downloads: 11 This Week
    Last Update:
    See Project
  • 25
    mitmproxy

    mitmproxy

    A free and open source interactive HTTPS proxy

    mitmproxy is an open source, interactive SSL/TLS-capable intercepting HTTP proxy, with a console interface fit for HTTP/1, HTTP/2, and WebSockets. It's the ideal tool for penetration testers and software developers, able to debug, test, and make privacy measurements. It can intercept, inspect, modify and replay web traffic, and can even prettify and decode a variety of message types. Its web-based interface mitmweb gives you a similar experience as Chrome's DevTools, with the addition of features like request interception and replay. Its command-line version mitmdump allows you to write powerful addons and script mitmproxy so it can automatically modify messages, redirect traffic, and perform many other custom commands.
    Downloads: 11 This Week
    Last Update:
    See Project
  • Previous
  • You're on page 1
  • 2
  • 3
  • 4
  • 5
  • Next
MongoDB Logo MongoDB