Authorization bypass in Grafana datasource deletion

Low

Summary

A time-of-create-to-time-of-use (TOCTOU) vulnerability lets recently deleted-then-recreated data sources be re-deleted without permission to do so.

This requires several very stringent conditions to be met:

The attacker must have admin access to the specific datasource prior to its first deletion.
Upon deletion, all steps within the attack must happen within the next 30 seconds and on the same pod of Grafana.
The attacker must delete the datasource, then someone must recreate it.
The new datasource must not have the attacker as an admin.
The new datasource must have the same UID as the prior datasource. These are randomised by default.
The datasource can now be re-deleted by the attacker.
Once 30 seconds are up, the attack is spent and cannot be repeated.
No datasource with any other UID can be attacked.

This vulnerability was reported to us via our bug bounty program by se1en.