fix(inspect): validate metadata URI before fetching (SSRF)#12
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`inspect` reads `metadataURI` from the on-chain registry, which any registrant can write, and fetched it with no checks. A hostile entry could point the fetch at an internal address (e.g. cloud metadata at 169.254.169.254) from the machine or CI runner that runs `inspect`. - Reject a metadata URI whose host is a private/internal address before fetching, reusing `isPrivateHostname`. - Reject non-http(s) schemes. - Add the link-local range (169.254.0.0/16, which covers the cloud metadata endpoint) to `PRIVATE_HOSTNAME_RE`; it was previously absent, so the endpoint probe did not flag it either. Adds a regression test that a link-local metadata URI is never fetched.
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What
inspectfetches the on-chainmetadataURIwith no validation. This validates it first so a hostile registry entry cannot point the fetch at an internal address.Why
metadataURIis read from the tool registry, which any party can write to permissionlessly, andinspectpasses it straight tofetch(src/cli/commands/inspect.ts). A registrant can storehttp://169.254.169.254/latest/meta-data/...and post the tool id; a developer or CI runner that runstool-sdk inspect --tool-id <id>then issues that request to the cloud metadata endpoint from inside the trust boundary. TheisPrivateHostnameguard already exists (it is applied tomanifest.endpoint) but was never applied tometadataURI, and itsPRIVATE_HOSTNAME_REdid not cover the link-local range the metadata endpoint lives in.Change
metadataURIbefore fetching: reject a private/internal host (reusingisPrivateHostname) and reject non-http(s)schemes.169.254.0.0/16(which contains169.254.169.254) toPRIVATE_HOSTNAME_RE, so the endpoint probe flags it too.Tests
Adds a regression test that a link-local
metadataURIis never fetched. Against the current code it fails (the address is fetched):With the fix it passes and the full suite stays green: