analyzing-persistence-mechanisms-in-linux

Detect and analyze Linux persistence mechanisms including crontab entries, systemd service units, LD_PRELOAD hijacking, bashrc modifications, and authorized_keys backdoors using auditd and file integrity monitoring

16 stars

Best use case

analyzing-persistence-mechanisms-in-linux is best used when you need a repeatable AI agent workflow instead of a one-off prompt.

Detect and analyze Linux persistence mechanisms including crontab entries, systemd service units, LD_PRELOAD hijacking, bashrc modifications, and authorized_keys backdoors using auditd and file integrity monitoring

Teams using analyzing-persistence-mechanisms-in-linux should expect a more consistent output, faster repeated execution, less prompt rewriting.

When to use this skill

  • You want a reusable workflow that can be run more than once with consistent structure.

When not to use this skill

  • You only need a quick one-off answer and do not need a reusable workflow.
  • You cannot install or maintain the underlying files, dependencies, or repository context.

Installation

Claude Code / Cursor / Codex

$curl -o ~/.claude/skills/analyzing-persistence-mechanisms-in-linux/SKILL.md --create-dirs "https://raw.githubusercontent.com/plurigrid/asi/main/plugins/asi/skills/analyzing-persistence-mechanisms-in-linux/SKILL.md"

Manual Installation

  1. Download SKILL.md from GitHub
  2. Place it in .claude/skills/analyzing-persistence-mechanisms-in-linux/SKILL.md inside your project
  3. Restart your AI agent — it will auto-discover the skill

How analyzing-persistence-mechanisms-in-linux Compares

Feature / Agentanalyzing-persistence-mechanisms-in-linuxStandard Approach
Platform SupportNot specifiedLimited / Varies
Context Awareness High Baseline
Installation ComplexityUnknownN/A

Frequently Asked Questions

What does this skill do?

Detect and analyze Linux persistence mechanisms including crontab entries, systemd service units, LD_PRELOAD hijacking, bashrc modifications, and authorized_keys backdoors using auditd and file integrity monitoring

Where can I find the source code?

You can find the source code on GitHub using the link provided at the top of the page.

SKILL.md Source

# Analyzing Persistence Mechanisms in Linux

## Overview

Adversaries establish persistence on Linux systems through crontab jobs, systemd service/timer units, LD_PRELOAD library injection, shell profile modifications (.bashrc, .profile), SSH authorized_keys backdoors, and init script manipulation. This skill scans for all known persistence vectors, checks file timestamps and integrity, and correlates findings with auditd logs to build a timeline of persistence installation.


## When to Use

- When investigating security incidents that require analyzing persistence mechanisms in linux
- When building detection rules or threat hunting queries for this domain
- When SOC analysts need structured procedures for this analysis type
- When validating security monitoring coverage for related attack techniques

## Prerequisites

- Root or sudo access on target Linux system (or forensic image)
- auditd configured with file watch rules on persistence paths
- Python 3.8+ with standard library (os, subprocess, json)
- Optional: OSSEC/Wazuh agent for file integrity monitoring alerts

## Steps

1. **Scan Crontab Entries** — Enumerate all user crontabs, /etc/cron.d/, /etc/cron.daily/, and anacron jobs for suspicious commands
2. **Audit Systemd Units** — Check /etc/systemd/system/ and ~/.config/systemd/user/ for non-package-managed service and timer units
3. **Detect LD_PRELOAD Hijacking** — Check /etc/ld.so.preload and LD_PRELOAD environment variable for injected shared libraries
4. **Inspect Shell Profiles** — Scan .bashrc, .bash_profile, .profile, /etc/profile.d/ for injected commands or reverse shells
5. **Check SSH Authorized Keys** — Audit all authorized_keys files for unauthorized public keys with command restrictions
6. **Correlate Auditd Logs** — Search auditd logs for file modification events on persistence paths to build an installation timeline
7. **Generate Persistence Report** — Produce a risk-scored report of all discovered persistence mechanisms

## Expected Output

- JSON report of all persistence mechanisms found with risk scores
- Timeline of persistence installation from auditd correlation
- MITRE ATT&CK technique mapping (T1053, T1543, T1574, T1546)
- Remediation commands for each detected persistence mechanism

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