# Persistence

> Cron, SSH keys, web shells, backdoors, systemd, and profile persistence

- **URL:** https://hackindex.io/platforms/linux/persistence
- **Platform:** [Linux](https://hackindex.io/platforms/linux.md)
- **Published:** 2026-04-04
- **Updated:** 2026-04-30

Linux persistence ensures you maintain access to a compromised system across reboots and user sessions. Techniques range from simple cron jobs and SSH authorized key additions to more advanced methods like malicious systemd services, init script modifications, LD_PRELOAD hijacking, and PAM backdoors.

The subpages cover each persistence mechanism, when to use it, and how to keep it from being easily detected during incident response.

## Guides

- [Linux Backdoor Account Persistence](https://hackindex.io/platforms/linux/persistence/linux-backdoor-account-persistence.md): Covers techniques for detecting and preventing unauthorized backdoor accounts on Linux systems used to maintain persistent unauthorized access.
- [Linux Cron and Timer Persistence](https://hackindex.io/platforms/linux/persistence/linux-cron-and-timer-persistence.md): Covers abusing cron jobs and systemd timers to maintain persistent access on Linux systems, including scheduled task backdoors and detection evasion.
- [Linux Shell and Profile Persistence](https://hackindex.io/platforms/linux/persistence/linux-shell-and-profile-persistence.md): Techniques for maintaining persistent access on Linux systems via shell configuration files, profile scripts, and environment variable hijacking.
- [Linux SSH Authorized Keys Persistence](https://hackindex.io/platforms/linux/persistence/linux-ssh-authorized-keys-persistence.md): Covers abusing SSH authorized_keys files to maintain persistent backdoor access on Linux systems by injecting attacker-controlled public keys.
- [Linux Systemd Service Persistence](https://hackindex.io/platforms/linux/persistence/linux-systemd-service-persistence.md): Covers creating malicious systemd service units to maintain persistent code execution across reboots, including unit file structure and enabling techniques.
- [Linux Web Shell Persistence](https://hackindex.io/platforms/linux/persistence/linux-web-shell-persistence.md): Covers techniques attackers use to deploy and maintain web shells on Linux servers for persistent backdoor access and remote code execution.