Textream is a free macOS teleprompter app. Prior to version 1.5.1, the DirectorServer WebSocket server imposes no limit on concurrent connections. Combined with a broadcast timer that sends state to all connected clients every 100 ms, an attacker can exhaust CPU and memory by flooding the server with connections, causing the Textream application to freeze and crash during a live session. Version 1.5.1 fixes the issue.
The product does not properly control the allocation and maintenance of a limited resource.
| Name | Vendor | Start Version | End Version |
|---|---|---|---|
| Textream | Fka | * | 1.5.1 (excluding) |
Mitigation of resource exhaustion attacks requires that the target system either:
The first of these solutions is an issue in itself though, since it may allow attackers to prevent the use of the system by a particular valid user. If the attacker impersonates the valid user, they may be able to prevent the user from accessing the server in question.
The second solution is simply difficult to effectively institute – and even when properly done, it does not provide a full solution. It simply makes the attack require more resources on the part of the attacker.