11. A system for estimating confidence scores of unverified signatures, the system comprising: a detection module, stored in memory, that: detects a potentially malicious event that triggers a malware signature designed to detect malware, the malware signature having a confidence score that: represents a level of confidence in the accuracy or reliability of the malware signature; and is above a certain threshold such that the malware signature's confidence score indicates a threshold level of confidence in the accuracy or reliability of the malware signature; detects another event that triggers another signature designed to detect malware, the other signature having a confidence score that: represents a level of confidence in the accuracy or reliability of the other signature; and is unknown such that the other signature's confidence score indicates an unknown level of confidence in the accuracy or reliability of the other signature; a determination module, stored in memory, that determines that the potentially malicious event and the other event occurred within a certain time period of one another; a confidence module, stored in memory, that assigns, to the other signature, a confidence score based at least in part on the potentially malicious event and the other event occurring within the certain time period of one another; and at least one physical processor that executes the detection module, the determination module, and the confidence module.
18. The system of claim 11 , wherein: the detection module: detects one or more potentially malicious events that trigger one or more malware signatures whose confidence scores are above a certain threshold; and detects one or more instances of the other event that triggers the other signature whose confidence score is unknown; the determination module determines the number of the one or more potentially malicious events and the number of the one or more instances of the other event that occurred within a certain window of time; and the confidence module: calculates a confidence score for the other signature by dividing the number of the one or more potentially malicious events by the number of the one or more instances of the other event; and assigns, to the other signature, the confidence score calculated by dividing the number of the one or more potentially malicious events by the number of the one or more instances of the other event.