deta/surf: technical due diligence, read from its repository

The median source file here is 57 lines. 15 files exceed 1,000 lines, the largest being 2,830. Size is not a defect on its own — some problems genuinely live in one place — but these are where merge conflicts, review fatigue and single-owner knowledge concentrate, and they are the first thing that slows an inheriting engineer down.

3 third-party CI actions are referenced by a tag or branch rather than a commit, so they run whatever that tag points to on the day. Tags have been moved to malicious commits in real supply-chain attacks, and a piped script is whatever the server returns that minute. Pinning to a commit is the fix, and it is small.

2 places run a command through a shell (`shell=True`, `os.system`, `exec` with a template) rather than passing arguments. Where any part comes from outside, it is command injection. Ask where each one's input comes from.

69 of 2,043 locked dependencies match 168 published advisories in OSV, 73 of them rated high or critical. A lockfile says which version is installed, not whether the flawed code is reachable from this product, so each needs a look. Most are fixed by an upgrade, and the advisory names the version. None of the high or critical ones is in what the product ships: 2 apply only under a condition the advisory states, which a lockfile cannot settle. This lockfile pins development tools alongside what ships and does not say which is which, so some of these may never reach a user.

12 places set HTML from a value that is neither a literal nor passed through a sanitiser. Where the value can come from a user, that is stored cross-site scripting, and it is the first thing a buyer's security review looks for in a frontend.