Security

Quartermaster takes payments but never takes custody, and it fetches URLs you give it without becoming a proxy into private networks. Here is how.

Payments: no custody

The receiving wallet is receive-only. Quartermaster never holds a spending key for customer funds and cannot move, hold, or trade anyone's money.
Settlement runs through a standard x402 facilitator on Base mainnet; verification and settlement are on-chain and publicly auditable.
No trading, swapping, lending, or investment logic exists anywhere in the product.

Request safety (SSRF hardening)

Tools that fetch a URL you supply (extract, meta, the x402 inspector and audit) validate the target before and after redirects:

Only http and https are allowed. localhost, .local/.internal hosts, and private/link-local IP ranges are blocked.
Blocks common SSRF encodings: IPv4-mapped IPv6 (::ffff:...), and decimal- and hex-encoded IPv4.
The landing host is re-validated after redirects, so a 30x to an internal address is refused, not followed.
Requests are time-limited and body-size-capped; the service refuses to fetch itself.

Verify what you install

The Quartermaster Lens browser extension is read-only (no keys, no signing, no custody). Verify the binaries by SHA-256:

Firefox .xpi (v1.0.1)   adafd94dd0b0c122497fa508a222fa117ba07640075020f2f674b42d38389464
Source .zip (v1.1.2)    6b0898b5ba0641ca3e0c41889ff7cda90d0ef1ce36170c7936bd448f4cf1a995

Signing keys

The MCP registry publisher key (ed25519) is published at /.well-known/mcp-registry-auth. Discovery ownership proofs are served under /.well-known/.

Responsible disclosure

Found something? Email dev@surewhynot.app with details and steps to reproduce. We will acknowledge and fix; no bug-bounty program yet, but credit is given.