This policy covers ProtocolCanary-Fixtures: the fixture files, JSON schemas, and the structural validator under tools/validate/. It does not cover StellarCanary/Protocol-Canary (the engine that consumes these fixtures), which has its own security policy.

This repository is public, and its fixtures are consumed by a tool that may run in a project's CI pipeline. Every fixture file must be treated as untrusted input by any consumer, including Protocol-Canary itself:

• No executable fixture code. Fixture files are TOML data. There is no shell_command, exec, script, command, pre_run, or post_run field, and none will be added. A pull request introducing one will be rejected regardless of stated purpose.
• No secrets. No fixture may contain a private key, seed phrase, or funded-account secret. The soroban surface's source_account field is a public account address only, used to build an unsigned transaction for simulation — never one that is signed or submitted.
• No transaction submission. Fixtures may require decoding, encoding, or read-only RPC calls (getNetwork, getLatestLedger) or Soroban simulation. No fixture may cause Protocol-Canary to submit a state-changing transaction to any network.
• Parser-safety in mind. decode-failure fixtures deliberately feed malformed input to an XDR decoder; when adding one, prefer inputs that exercise a specific, documented rejection (truncation, an invalid discriminant) over arbitrary fuzzing payloads, and note in the fixture's header comment what kind of malformation it demonstrates.

tools/validate/validate.py only reads fixture files and reports structural problems (schema conformance, duplicate IDs, missing files). It never executes a fixture's assertion and never makes a network call.

The validator also enforces provenance rather than merely advising on it: a fixture with no source_reference (or an empty one) is reported as an error, so it fails validation and therefore CI, instead of passing with a printed warning. This makes the shared validator — not a pack-specific test — the common enforcement point for the claim that every assertion is traceable to an authoritative upstream source.

No formal third-party security audit has been performed on this repository. Confidence in the "fixtures are data, not code" claim comes from the fixture schema itself (no executable field exists) and the validator's tests, not from an external review. Confidence in fixture provenance comes from the structural validator, which treats a missing source_reference as an error (see above).

If you find a security issue in this repository — a fixture that could be used to smuggle executable content past a consumer's TOML parser, a schema gap that would let an untrusted .toml file crash a validator, or similar — please open a private report via GitHub's "Report a vulnerability" feature on this repository rather than filing a public issue. Include a description of the issue, its impact, and steps to reproduce.

These are best-effort targets for a small project with no paid on-call rotation, not a contractual SLA — but they are the times to hold us to. If a window above passes with no reply, please follow up in the same private report thread instead of disclosing publicly: a missed window means we lost track of the report, not that it was dismissed or out of scope.

Disclosure is coordinated with you, never unilateral on either side: we agree a date before any public write-up, and we will credit you in the fix's release notes unless you would rather stay anonymous.