Manifold Markets MCP

All 5 findings

1. high
   Tool `get-bets` accepts an unbounded monetary / quota value· get-betsexcessive agency

   The numeric parameter(s) `minAmount` have a money/quota-shaped name but no `maximum` constraint. An LLM tricked by indirect-injection can call the tool with arbitrarily large values.

   fix: Add a `maximum` (and ideally `minimum`) to each money/quota numeric, OR enforce the cap via a capframe-bind `--limit` caveat at the agent boundary.

2. medium
   Tool `search-markets` accepts unconstrained string input· search-marketsunconstrained input

   The following string parameter(s) have no `maxLength` constraint: `contractType`, `creatorId`, `filter`, `sort`, `term`. Unbounded strings let an attacker stuff arbitrary payloads through the tool, including indirect-injection content.

   fix: Add a `maxLength` to each string property, or constrain with an `enum` or `pattern`. Most legitimate tool inputs fit under a few hundred bytes.

3. medium
   Tool `get-market` accepts unconstrained string input· get-marketunconstrained input

   The following string parameter(s) have no `maxLength` constraint: `id`. Unbounded strings let an attacker stuff arbitrary payloads through the tool, including indirect-injection content.

   fix: Add a `maxLength` to each string property, or constrain with an `enum` or `pattern`. Most legitimate tool inputs fit under a few hundred bytes.

4. medium
   Tool `get-user` accepts unconstrained string input· get-userunconstrained input

   The following string parameter(s) have no `maxLength` constraint: `username`. Unbounded strings let an attacker stuff arbitrary payloads through the tool, including indirect-injection content.

   fix: Add a `maxLength` to each string property, or constrain with an `enum` or `pattern`. Most legitimate tool inputs fit under a few hundred bytes.

5. medium
   Tool `search-users` accepts unconstrained string input· search-usersunconstrained input

   The following string parameter(s) have no `maxLength` constraint: `term`. Unbounded strings let an attacker stuff arbitrary payloads through the tool, including indirect-injection content.

   fix: Add a `maxLength` to each string property, or constrain with an `enum` or `pattern`. Most legitimate tool inputs fit under a few hundred bytes.