Security: Unbounded limit parameter in user search can be abused for resource exhaustion#8476
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The `index(string $filter = '', int $limit = 5)` method accepts client-controlled `limit` and passes it directly to collaborator search. Without an upper bound, an attacker can request very large limits, causing expensive directory lookups and increased response size. Signed-off-by: tomaioo <203048277+tomaioo@users.noreply.github.com>
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Summary
Security: Unbounded
limitparameter in user search can be abused for resource exhaustionProblem
Severity:
Medium| File:lib/Controller/UserApiController.php:L39The
index(string $filter = '', int $limit = 5)method accepts client-controlledlimitand passes it directly to collaborator search. Without an upper bound, an attacker can request very large limits, causing expensive directory lookups and increased response size.Solution
Enforce a strict maximum (e.g., 10-50) for
limitbefore invoking search, and consider server-side rate limiting for this endpoint.Changes
lib/Controller/UserApiController.php(modified)