This server holds a personal API key that can read and (when enabled) change a live Splitwise account, and it can be exposed over HTTP behind a bearer token. This page covers how to report a vulnerability, what counts as one, and how to run the server safely.

Do not open a public issue, pull request or discussion. Report privately through GitHub:

1. Open the repository's Security tab → Report a vulnerability (direct link: https://github.com/trustxai/splitwise-mcp/security/advisories/new).
2. Include:
   • the version you ran (the PyPI release, e.g. 0.1.0, or the commit SHA);
   • the settings involved — variable names only, e.g. whether SPLITWISE_ALLOW_WRITES was set or which transport was running;
   • the tool calls and steps to reproduce, and what an attacker gains.

Never include real credentials — no API keys, bearer tokens or account identifiers. Build proofs of concept with mocked responses (the test suite uses httpx.MockTransport and httpx.ASGITransport). If a live key ends up in a report anyway, regenerate it at https://secure.splitwise.com/apps right away: a key that has been shared is compromised.

The project has a single maintainer, so these are targets, not guarantees:

Once the fix is on PyPI, a GitHub Security Advisory is published (with a CVE when warranted) and the CHANGELOG entry links to it. Reporters are credited in the advisory unless they ask not to be. Please keep the details private until the advisory is out.

Only the latest release on PyPI receives fixes.

• A way to change account state while SPLITWISE_ALLOW_WRITES is off.
• A way to change the account's email or password through any tool.
• A request reaching the HTTP transport without the bearer, or the bearer being recoverable from a response, a log line or an error message.
• The API key or the bearer appearing in any tool output, log or error.
• Anything that makes the server send a write Splitwise did not confirm as successful while reporting it as done.

• Keep SPLITWISE_ALLOW_WRITES unset unless the client genuinely needs to write.
• Never expose amazing-splitwise-mcp-http without TLS in front of it and a bearer of at least 32 random characters (openssl rand -hex 32); keep it bound to loopback and set SPLITWISE_MCP_ALLOWED_HOSTS to the hostname your proxy forwards.
• Rotate the API key on the Splitwise apps page and the bearer wherever it is configured (environment file, the client's connector) if either is ever exposed.