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Level 1 → Level 2

Sudo Allowlist · 320 pts · +50 first-blood bonus

First Blood Available

Mission

This challenge contains a permissive sudo rule on a standard Linux utility. An unprivileged user can use the rule to execute arbitrary code as root. To solve the challenge, read /flag.

Starting toolkit (you may need more)

sudo

Why this matters in 2026

Sudo allowlists containing binaries that were never meant to live in an allowlist are the number-one finding in real Linux hardening audits. Every defender must learn to read sudoers the way an attacker does.

Mitigation era: 2026-04 · rotation policy: levels may be refreshed as CVEs are patched out of distro defaults.

How to reach this level

Use the password for phantom1 that you captured on the previous level, then:

ssh phantom1@phantom.breachlab.org -p 2223

SSH endpoint is being provisioned. Follow @BreachLab for launch announcement.

Log in to submit flags and track progress.