Level 9 → Level 10

Writable Rules · 580 pts · +50 first-blood bonus

First Blood Available

Mission

This challenge contains a directory that is meant to hold additional sudo configuration files. An unprivileged user has write access to that directory. To solve the challenge, read /flag.

Starting toolkit (you may need more)

lssudo

Why this matters in 2026

Misconfigured permissions on sudo include directories are a surprisingly common finding in container base images and quickly-built developer VMs. A single writable directory here is a one-line end-to-end root.

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 phantom9 that you captured on the previous level, then:

ssh phantom9@phantom.breachlab.org -p 2223

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