The new broker pallet, responsible for handling the Coretime procurement logic, had a vulnerability that allowed users to assign Coretime they no longer owned. This is, obviously, quite problematic.

The issue is described in more detail here: https://github.com/paritytech/polkadot-sdk/pull/2811

This is a small tip request for finding reporting and fixing the issue.

Problem Statement:
- The new broker pallet had a vulnerability that allowed users to assign Coretime they no longer owned, posing a problem.

Significance:
- The vulnerability in the broker pallet could lead to incorrect assignment of Coretime, potentially causing financial losses or disruptions in the Polkassembly system.

Proposed Solution:
- A tip request is made to find and report the vulnerability in order to fix it.

Expected Outcomes:
- Identification and resolution of the vulnerability in the broker pallet to ensure accurate and secure assignment of Coretime in the Polkassembly system.

#393 Finding and fixing a vulnerability in broker-pallet