The qs module before 1.0.0 does not have an option or default for specifying object depth and when parsing a string representing a deeply nested object will block the event loop for long periods of time. An attacker could leverage this to cause a temporary denial-of-service condition, for example, in a web application, other requests would not be processed while this blocking is occurring.
The product does not properly control the allocation and maintenance of a limited resource.
| Name | Vendor | Start Version | End Version |
|---|---|---|---|
| Qs | Qs_project | * | 1.0.0 (excluding) |
| Node-qs | Ubuntu | artful | * |
| Node-qs | Ubuntu | esm-infra-legacy/trusty | * |
| Node-qs | Ubuntu | trusty | * |
| Node-qs | Ubuntu | trusty/esm | * |
| Node-qs | Ubuntu | upstream | * |
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.