Driftwood Analytics is a small SaaS shop, a dashboard over a few pipelines, run by a handful of engineers. In one bad week a dependency they trusted shipped a poisoned update: its install hook ran on the build server, beaconed the runner’s environment out as Base64, and from there the trouble spread. A CI token and a cloud key leaked, a stolen key made itself an admin, a storage bucket was found readable by anyone, a secret turned up baked into a shipped container image, and a container tunnelled data out over DNS. You have what the company kept: a package-lock and the install script, the CI run log, the egress proxy and resolver logs, CloudTrail, a bucket policy and object listing, a Dockerfile with an image layer, a git reflog dump, a captured token and a .env. Follow the thread from the dependency to the admin user. A few findings unlock the next step, and two questions reward reading slowly rather than pattern-matching.
Supply chain, essential, 75 points. A package-lock.json from the Driftwood app. Every dependency records the tarball it was resolved from. All but one resolve from npm’s own registry; that one is the poisoned update. Its deprecation notice carries a Base64 marker. Decode it to get the flag, in the form flag{...}.
Crypto, essential, 100 points. A value exported from the secrets store (secret.txt) has been through three encodings stacked on top of each other: the flag was hex-encoded, the hex was Base32-encoded, and that was Base64-encoded. Peel them off in the right order to read the flag, in the form flag{...}.
Web, essential, 75 points. A JWT (session.jwt) captured from the app. A JWT has three Base64url parts joined by dots, and the middle one is readable JSON, not a secret. Decode the payload and read the claims. A canary claim holds the flag, in the form flag{...}.
Reversing, intermediate, 150 points. The malicious package shipped a postinstall script. It hides its real code as an array of numbers run through String.fromCharCode, then eval. Turn the numbers back into text. The decoded script names the command-and-control host and carries the flag, in the form flag{...}.
CI/CD, intermediate, 150 points. A CI build log. The poisoned install hook ran on the runner and beaconed its environment out as a Base64 string in a URL (so the ::add-mask:: rules never matched it). Find the beacon, decode the blob, and read what left the build. A planted canary secret in there is the flag, in the form flag{...}.
OSINT, intermediate, 125 points. Four files pulled during the review: commit authors, support-ticket reporters, the on-call roster, and a recovery-code vault export. Exactly one login appears in all three identity lists. Find it, then decode that login’s recovery code from the vault to get the flag, in the form flag{...}. Use only these files.
Cloud, intermediate, 150 points. A bucket policy (bucket-policy.json) and an object listing (object-listing.json). The policy grants anonymous read on one prefix. That is meant for static assets, but something sensitive was written there. Find the exposed object, read the secret it holds, and submit it as flag{...}.
Forensics, intermediate, 150 points. A Dockerfile, the image history (docker history), and one extracted layer. The build copies an .env into the image and removes it in a later step, so the file is gone from the final filesystem, yet it still ships inside an earlier layer. Find it, read the leaked .env, and decode the canary value into the flag, in the form flag{...}. The other secrets in that file matter later.
Forensics, intermediate, 150 points. The forward-proxy access log (combined format) for the app tier. The server keeps calling out to the collector host you already found. One of those calls carries staged data in a query parameter; the others are heartbeats. Decode the staged blob to get the flag, in the form flag{...}. Beware look-alike flags planted in ordinary traffic.
Reasoning traps, intermediate, 150 points. An on-call alert names the time an anomaly was seen, in US Pacific time. The CloudTrail excerpt is in UTC, as CloudTrail always is. Which single API call does the alert actually refer to, and at what UTC time? Convert carefully. Submit flag{<eventName>_HHMM}, the event name and its UTC time with no colon, like flag{PutBucketPolicy_0914}.
Forensics, advanced, 200 points. A dump of git log --oneline, git reflog, and a few git show outputs from the app repo. A commit that added credentials was undone with a hard reset and replaced by a clean one, so it is gone from the branch history but not from the repo. Find the orphaned commit, read its diff, and decode the leaked token into the flag, in the form flag{...}.
Misc, advanced, 150 points. A secret-scanner dump with thousands of findings, many of them decoy flag{...} strings. Exactly one line is a real deploy-key recovery code with the format PREFIX-NNNN-LLLL-NNNN: the fixed deploy-key prefix, four digits, four capital letters, four digits. Find that code and submit it as flag{<code>}. The decoy flag{...} lines are not the answer.
Crypto, advanced, 250 points. The app ships config.enc, obscured with a short repeating-key XOR. The key is the CONFIG_KEY you pulled from the leaked .env, and every config begins with the same JSON schema header, so you can also recover the key from known plaintext. Decrypt the file; the flag is inside, in the form flag{...}.
Cloud, advanced, 250 points. A CloudTrail log from the Driftwood AWS account. The access key that leaked from CI was used from the attacker’s address to create a new IAM user and give it administrator rights. A routine user was also created that day. Which user did the attacker create? Submit flag{<userName>}.
Network, advanced, 250 points. A DNS query log from the resolver the app containers use. The compromised container could not reach the collector over HTTP, so it leaked data as DNS: each query put a numbered chunk in a label under the collector domain. Reassemble the chunks in order, decode them, and read the flag, in the form flag{...}.
Reasoning traps, advanced, 200 points. An IAM role policy and one question: may this role perform the action on the exact object named in question.txt? Evaluate it the way AWS does, not by the first matching Allow. Answer flag{allow_<prefix>_<role>} or flag{deny_<prefix>_<role>}, where <prefix> is the object’s top-level prefix and <role> is the role name, like flag{deny_restricted_deploy-role}.
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