# Install duo_unix with Homebrew, apk, apt, dnf, Nix Two-factor authentication for SSH. Version 2.2.3 via Homebrew; verified 2026-06-22. ## Install ```sh sudo av install brew:duo_unix ``` Additional install commands: ### macOS - Homebrew (100%): ```sh brew install duo_unix ``` Evidence: local Homebrew formula metadata ### Linux - apk (92%): ```sh sudo apk add duo_unix ``` Evidence: Alpine Linux edge package indexes: duo_unix from https://dl-cdn.alpinelinux.org/alpine/edge/community/x86_64/APKINDEX.tar.gz - Debian apt (92%): ```sh sudo apt install libduo-dev ``` Evidence: Debian stable package indexes: libduo-dev from https://deb.debian.org/debian/dists/stable/main/binary-amd64/Packages.xz - dnf (92%): ```sh sudo dnf install duo_unix ``` Evidence: Fedora Rawhide package metadata: duo_unix from https://dl.fedoraproject.org/pub/fedora/linux/development/rawhide/Everything/x86_64/os/repodata/e5ca8ce900cd68f5419e1c39ae517343100b306336cbaeb70a3c153121d95094-primary.xml.zst - Nix (92%): ```sh nix profile install nixpkgs#duo-unix ``` Evidence: nixpkgs package indexes: pkgs/by-name/du/duo-unix/package.nix from https://api.github.com/repos/NixOS/nixpkgs/git/trees/master?recursive=1 ## Package facts - **Package key:** brew:duo_unix - **Package manager:** Homebrew - **Package manager page:** - **Version:** 2.2.3 - **Source summary:** Two-factor authentication for SSH - **Homepage:** - **Repository:** - **Upstream docs:** - **License:** GPL-2.0-or-later - **Source archive:** - **Last updated:** 2026-06-22T14:03:12-07:00 - **Generated:** 2026-07-08T07:18:31+00:00 ## Executables - duo_unix_support.sh (cli) - login_duo (cli) - duo_unix_support.sh (alias) - login_duo (alias) ## Dependencies - openssl@3 ## Build dependencies - autoconf - automake - libtool ## Install behavior - Post-install hook: not defined - Bottle: available on arm64_linux, arm64_sequoia, arm64_sonoma, arm64_tahoe, sonoma, x86_64_linux ## Freshness - Page generated: 2026-07-08 - Package-manager version: 2.2.3 - Package-manager updated: 2026-06-22 - Local data: ok - Upstream repository: https://github.com/duosecurity/duo_unix - Upstream latest detected: duo_unix-2.2.3 (current) ## Project history and usage Duo Unix is Duo Security's Unix integration for adding Duo two-factor authentication to SSH, sudo, and other PAM-protected services. It packages two important surfaces: the `pam_duo` PAM module and the `login_duo` standalone login wrapper. ### Project history The public Duo Unix repository was created in 2011 and is maintained by Duo Security. The README describes it as Duo two-factor authentication for Unix systems, with the repository intended for development or cutting-edge versions while stable release tarballs and packages are recommended for production deployments. The project is written mainly in C and uses traditional Unix build machinery: bootstrap, configure, make, and make install. Its docs and README center on the practical security integration points: PAM, login wrappers, OpenSSL-backed TLS, and config files containing Duo integration keys and API host information. ### Adoption history Duo Unix adoption follows Duo's enterprise MFA adoption path: administrators add a Duo Unix integration in the Duo Admin Panel, deploy packages or stable tarballs, configure SSH or sudo, and place integration credentials in `/etc/duo` or `/etc/security` config files. Package metadata shows distribution through Homebrew, Alpine, Debian/Ubuntu development packages, Fedora, and Nix. That breadth matters because PAM integrations are usually installed by OS package managers on servers rather than vendored into applications. ### How it is used Typical usage is to install Duo Unix with PAM support, create a Unix integration in the Duo Admin Panel, put the integration key, secret key, and API hostname into `pam_duo.conf` or `login_duo.conf`, and then wire `pam_duo` into the PAM stack for SSH or sudo. `login_duo` can also protect command execution without PAM. The README shows a test invocation that runs a command only after successful Duo authentication. ### Why package nerds care Duo Unix is package-nerd significant because it lives at a high-risk boundary: a small C package, config files with secrets, PAM modules, and remote MFA API calls can affect whether administrators can log into their own machines. Its packaging history illustrates why security integrations stay conservative: upstream points production users at stable tarballs/packages, while the GitHub repo remains the development surface. For package managers, correct file placement and clear upgrade behavior matter as much as the executable. ### Timeline - 2011: The public duosecurity/duo_unix repository is created. - 2025: Duo Unix 2.1.0 and 2.2.x releases are published on GitHub. - 2026: The repository remains active with updates and package-manager distribution across multiple Unix-like systems. ### Related projects - Duo Security's Unix integration and Admin Panel are the operational counterpart to the open-source Unix package. - OpenPAM/Linux-PAM, OpenSSH, sudo, and OpenSSL are adjacent infrastructure because Duo Unix plugs into PAM-protected login flows and uses the system OpenSSL library for TLS. ### Sources - - - - ## Security Notes broad file, network, media, or database tool signal. - **Geiger risk:** blue / medium - broad file, network, media, or database tool signal ## Configuration and credential file locations These source-backed paths show where this package keeps local settings or durable credentials. Automic Vault can use them as review targets for secret scanning, migration, and command approval. ## Configuration files - Unix: /etc/duo/pam_duo.conf, /etc/security/pam_duo.conf, /etc/duo/login_duo.conf, /etc/security/login_duo.conf ## Credential files - Unix: /etc/duo/pam_duo.conf, /etc/security/pam_duo.conf, /etc/duo/login_duo.conf, /etc/security/login_duo.conf ## Source Database Details - **Source Database:** Homebrew formula API - **Tap:** homebrew/core - **Full Name:** duo_unix - **Version Scheme:** 0 - **Revision:** 0 - **Bottle Stable Root URL:** - **Deprecated:** no - **Disabled:** no - **Keg Only:** no - **URL Keys:** stable ## Other Package-Manager Records - Debian apt - libduo-dev - 1.11.3-1.2+b1: normalized package name match | Debian stable package indexes: libduo-dev from https://deb.debian.org/debian/dists/stable/main/binary-amd64/Packages.xz | Duo Security development libraries and header files | https://github.com/duosecurity/duo_unix - Debian apt - libduo3t64 - 1.11.3-1.2+b1: normalized package name match | Debian stable package indexes: libduo3t64 from https://deb.debian.org/debian/dists/stable/main/binary-amd64/Packages.xz | Duo Security library | https://github.com/duosecurity/duo_unix - Debian apt - libpam-duo - 1.11.3-1.2+b1: normalized package name match | Debian stable package indexes: libpam-duo from https://deb.debian.org/debian/dists/stable/main/binary-amd64/Packages.xz | PAM module for Duo Security two-factor authentication | https://github.com/duosecurity/duo_unix - Debian apt - login-duo - 1.11.3-1.2+b1: normalized package name match | Debian stable package indexes: login-duo from https://deb.debian.org/debian/dists/stable/main/binary-amd64/Packages.xz | login wrapper for Duo Security two-factor authentication | https://github.com/duosecurity/duo_unix - Nix - duo-unix: normalized package name match | nixpkgs package indexes: pkgs/by-name/du/duo-unix/package.nix from https://api.github.com/repos/NixOS/nixpkgs/git/trees/master?recursive=1 - Ubuntu apt - libduo-dev - 1.11.3-1.1build2: normalized package name match | Ubuntu 24.04 LTS package indexes: libduo-dev from https://archive.ubuntu.com/ubuntu/dists/noble/universe/binary-amd64/Packages.gz | Duo Security development libraries and header files | https://github.com/duosecurity/duo_unix - Ubuntu apt - libduo3t64 - 1.11.3-1.1build2: normalized package name match | Ubuntu 24.04 LTS package indexes: libduo3t64 from https://archive.ubuntu.com/ubuntu/dists/noble/universe/binary-amd64/Packages.gz | Duo Security library | https://github.com/duosecurity/duo_unix - Ubuntu apt - libpam-duo - 1.11.3-1.1build2: normalized package name match | Ubuntu 24.04 LTS package indexes: libpam-duo from https://archive.ubuntu.com/ubuntu/dists/noble/universe/binary-amd64/Packages.gz | PAM module for Duo Security two-factor authentication | https://github.com/duosecurity/duo_unix - Ubuntu apt - login-duo - 1.11.3-1.1build2: normalized package name match | Ubuntu 24.04 LTS package indexes: login-duo from https://archive.ubuntu.com/ubuntu/dists/noble/universe/binary-amd64/Packages.gz | login wrapper for Duo Security two-factor authentication | https://github.com/duosecurity/duo_unix - apk - duo_unix - 1.12.1-r2: normalized package name match | Alpine Linux edge package indexes: duo_unix from https://dl-cdn.alpinelinux.org/alpine/edge/community/x86_64/APKINDEX.tar.gz | Duo two-factor authentication for Unix systems with Pluggable Authentication Modules (PAM) | https://duo.com/docs/duounix - apk - duo_unix-dev - 1.12.1-r2: normalized package name match | Alpine Linux edge package indexes: duo_unix-dev from https://dl-cdn.alpinelinux.org/alpine/edge/community/x86_64/APKINDEX.tar.gz | Duo two-factor authentication for Unix systems with Pluggable Authentication Modules (PAM) (development files) | https://duo.com/docs/duounix - apk - duo_unix-doc - 1.12.1-r2: normalized package name match | Alpine Linux edge package indexes: duo_unix-doc from https://dl-cdn.alpinelinux.org/alpine/edge/community/x86_64/APKINDEX.tar.gz | Duo two-factor authentication for Unix systems with Pluggable Authentication Modules (PAM) (documentation) | https://duo.com/docs/duounix - dnf - duo_unix - 2.2.3-1.fc44: normalized package name match | Fedora Rawhide package metadata: duo_unix from https://dl.fedoraproject.org/pub/fedora/linux/development/rawhide/Everything/x86_64/os/repodata/e5ca8ce900cd68f5419e1c39ae517343100b306336cbaeb70a3c153121d95094-primary.xml.zst | Duo two-factor authentication for UNIX systems | https://duo.com/ - dnf - duo_unix-devel - 2.2.3-1.fc44: normalized package name match | Fedora Rawhide package metadata: duo_unix-devel from https://dl.fedoraproject.org/pub/fedora/linux/development/rawhide/Everything/x86_64/os/repodata/e5ca8ce900cd68f5419e1c39ae517343100b306336cbaeb70a3c153121d95094-primary.xml.zst | Development files and documentation for duo_unix | https://duo.com/ - dnf - duo_unix-doc - 2.2.3-1.fc44: normalized package name match | Fedora Rawhide package metadata: duo_unix-doc from https://dl.fedoraproject.org/pub/fedora/linux/development/rawhide/Everything/x86_64/os/repodata/e5ca8ce900cd68f5419e1c39ae517343100b306336cbaeb70a3c153121d95094-primary.xml.zst | Documentation and license files for duo_unix | https://duo.com/ - dnf - duo_unix-selinux - 2.2.3-1.fc44: normalized package name match | Fedora Rawhide package metadata: duo_unix-selinux from https://dl.fedoraproject.org/pub/fedora/linux/development/rawhide/Everything/x86_64/os/repodata/e5ca8ce900cd68f5419e1c39ae517343100b306336cbaeb70a3c153121d95094-primary.xml.zst | SELinux rules for duo_unix | https://duo.com/ ## Related links - [Secret-risk packages](https://www.automicvault.com/pkg/secret-risk-packages/) - Has protected-tool coverage, approval-gate, or non-low Geiger security signals. - [Terminal utility packages](https://www.automicvault.com/pkg/terminal-utilities/) - Matched terminal and command-line workflow metadata. - [Networking and protocol packages](https://www.automicvault.com/pkg/networking-protocol-tools/) - Matched network, protocol, or remote-service metadata. - [Security and crypto packages](https://www.automicvault.com/pkg/security-crypto-tools/) - Matched security, identity, cryptography, password, signing, or certificate metadata. - [openssl@3](https://www.automicvault.com/pkg/brew/openssl-3/) - Runtime dependency declared by Homebrew. - [autoconf](https://www.automicvault.com/pkg/brew/autoconf/) - Build dependency declared by Homebrew. - [automake](https://www.automicvault.com/pkg/brew/automake/) - Build dependency declared by Homebrew. - [libtool](https://www.automicvault.com/pkg/brew/libtool/) - Build dependency declared by Homebrew. - [google-authenticator-libpam](https://www.automicvault.com/pkg/brew/google-authenticator-libpam/) - Shares av.db curated category or tags: authentication, cli, pam, security, two-factor-authentication. - [linux-pam](https://www.automicvault.com/pkg/brew/linux-pam/) - Shares av.db curated category or tags: authentication, cli, pam, security. - [oath-toolkit](https://www.automicvault.com/pkg/brew/oath-toolkit/) - Shares av.db curated category or tags: authentication, cli, pam, security. - [cotp](https://www.automicvault.com/pkg/brew/cotp/) - Shares av.db curated category or tags: authentication, cli, security, two-factor-authentication. - [cyrus-sasl](https://www.automicvault.com/pkg/brew/cyrus-sasl/) - Shares av.db curated category or tags: authentication, cli, security. - [gauth](https://www.automicvault.com/pkg/brew/gauth/) - Shares av.db curated category or tags: authentication, cli, security, two-factor-authentication. - [krb5](https://www.automicvault.com/pkg/brew/krb5/) - Shares av.db curated category or tags: authentication, cli, security. - [monkeysphere](https://www.automicvault.com/pkg/brew/monkeysphere/) - Shares av.db curated category or tags: authentication, cli, security, ssh. - [pam-u2f](https://www.automicvault.com/pkg/brew/pam-u2f/) - Security-sensitive metadata or terminology overlaps. Shared terms: authentication, cli, openssl, openssl-3, pam. ## Combined YAML source View the package source record on GitHub. [combined/duo_unix.yml](https://github.com/automic-vault/db/blob/main/combined/duo_unix.yml) ## Sources - Nucleus package database - Geiger risk classifier - package-page enrichment - curated configuration and credential file locations - curated package history - package version freshness - av.db category and tag curation - package relationship graph - external package-manager database matches - cross-ecosystem install command graph