Rhino is an open-source implementation of JavaScript written entirely in Java. Prior to 1.8.1, 1.7.15.1, and 1.7.14.1, when an application passed an attacker controlled float poing number into the toFixed() function, it might lead to high CPU consumption and a potential Denial of Service. Small numbers go through this call stack: NativeNumber.numTo > DToA.JS_dtostr > DToA.JS_dtoa > DToA.pow5mult where pow5mult attempts to raise 5 to a ridiculous power. This vulnerability is fixed in 1.8.1, 1.7.15.1, and 1.7.14.1.
The product does not properly control the allocation and maintenance of a limited resource.
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.