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MakeSense

Hack The Box · app.hackthebox.com/machines/MakeSense
Linux Medium Season 11 ● Completed writeup after season
Summary User flag fell fast; root was the interesting part. The obvious lead — a package-manager service whose version matched a recent high-severity local-privesc CVE — turned into a rabbit hole. The real root cause was an access-control gap in a custom application: a low-privileged account could write a file into a directory consumed by a process running as root. No memory corruption, no race — just a broken trust boundary.

01Why the full writeup is held back

MakeSense is a live Season 11 machine. In line with Hack The Box's guidance on active machines, I don't publish a step-by-step reproduction while it's still in play. The complete writeup — recon, foothold, the CVE red-herring, the file-write-to-root vector, and remediation — goes live here once the season closes.

02The interesting bit (no spoilers)

A CVE that looked like the answer — and wasn't

A service on the box matched a recently disclosed, high-severity local privilege-escalation CVE. It looked like the intended path, so I invested time building and tuning an exploit. The catch: the vendor's fix had been silently backported into the distro package without a version bump — --version reported "vulnerable" while the changelog said otherwise. A good reminder that a version string is a claim, not proof.

The bug that actually worked

Root came from a custom internal tool with a file-write flaw — an ordinary access-control gap letting an unprivileged user drop a file where a root process would act on it. The "boring" class of bug (file writes, path handling, service trust boundaries) doing what boring bugs do best.

03Takeaways

Coming after Season 11 Full technical walkthrough with the exact chain, commands, and a remediation section.

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