These labs are safe simulations: the data, the login form, the firewall and the server are all fake and run only in your browser. Finish a lab to earn points.
Phishing inspector Six emails land in your inbox. Decide which are phishing and learn the warning signs.
Cybersecurity
Beginner SQL injection login Break into a deliberately vulnerable login form, then fix it with a parameterized query.
Software development
Intermediate Firewall rule builder Configure rules so the website is public, SSH is admin-only and the database stays private.
Networking
Intermediate Linux incident terminal Use a simulated shell to investigate an SSH attack in the logs and lock down a secret file.
Cloud & Linux
Beginner Cross-site scripting (XSS) Inject a script into a fake comment box, then switch on output escaping to stop it.
Software development
Intermediate Log detective Read a web server access log and answer questions about a scanner and an injection attempt.
Cybersecurity
Intermediate Password hash cracking See how a leaked database of weak password hashes falls to a lookup table, and how salting stops it.
Cybersecurity
Intermediate Cloud misconfiguration audit Review nine cloud settings and flag the risky ones before an attacker does.
Cloud & Linux
Beginner
Web server permissions Use the shell to find a world-writable file, a leaked password and fix the permissions.
Cloud & Linux
Intermediate Subnetting practice Seven calculation questions on hosts, network addresses, masks and ranges.
Networking
Intermediate Incident response order Put the six phases of incident response into the right order.
Cybersecurity
Beginner Name that malware Read six incident reports and decide which type of malware caused each one.
Cybersecurity
Beginner Social engineering tricks Six attempts to fool employees. Name the trick used in each one.
Cybersecurity
Beginner OWASP Top 10 triage Six bug reports from a penetration test. Sort each one into its OWASP Top 10 category.
Cybersecurity
Intermediate Cyber Kill Chain Put the seven stages of a targeted attack into the right order.
Cybersecurity
Intermediate Authentication factors Sort seven ways of proving who you are into know, have and are.
Cybersecurity
Beginner Strong or weak password? Judge seven passwords the way an attacker's cracking tool would.
Cybersecurity
Beginner OSI layer sorter Place seven everyday network things on the right layer of the OSI model.
Port numbers drill Type the standard port number for seven common services.
DNS record picker Six tasks for a new domain. Choose the DNS record type that does each job.
Networking
Intermediate TCP connection lifecycle Order the six steps of opening, using and closing a TCP connection.
Private or public IP? Classify seven IP addresses as private, public, loopback or link-local.
Networking
Intermediate HTTP status codes Seven API situations. Choose the status code a well-built server should return.
Software development
Beginner Git pull request workflow Put the eight steps of contributing a change with Git into the right order.
Software development
Beginner Secure code review Review eight lines of code and flag the ones that open a security hole.
Software development
Intermediate REST API methods Match six API actions to the right HTTP method.
Software development
Beginner Big-O complexity Estimate how six common operations slow down as the data grows.
Software development
Intermediate chmod number practice Convert six permission strings like rwxr-xr-x into their chmod numbers.
Cloud & Linux
Intermediate Linux command recall Type the Linux command for eight everyday server tasks.
Cloud & Linux
Beginner Shared responsibility model You rent virtual machines (IaaS). Decide who is responsible for seven security tasks.
Cloud & Linux
Intermediate IaaS, PaaS or SaaS? Sort six cloud services into infrastructure, platform or software as a service.
Cloud & Linux
Beginner 