A user with Viewer permissions can use specially crafted requests to the Tempo and Loki data source plugins to reach unintended backend endpoints. Depending on the backend configuration this can expose data source credentials, leak internal responses, or trigger administrative actions on the configured backend.

A TraceQL query in Grafana Tempo with a large exemplars hint value can cause the Tempo instance to allocate an excessive amount of memory, resulting in an out-of-memory crash. This could allow an authenticated user to trigger a denial of service against the Tempo service.

Tempo queries with large limits can cause large memory allocations which can impact the availability of the service, depending on its deployment strategy.

Mitigation can be done by setting maxresultlimit in the search config, e.g. to 262144 (2^18).

A vulnerability in Grafana Tempo exposes the S3 SSE-C encryption key in plaintext through the /status/config endpoint, potentially allowing unauthorized users to obtain the key used to encrypt trace data stored in S3.

Thanks to williamgoodfellow for reporting this vulnerability.