Abstract: Systems and methods for user-agent anomaly detection are disclosed. In one embodiment, a user-agent string may be embedded into a numerical data vector representation using a sentence embedding algorithm (e.g., FastText). A predictive score may be calculated based on the numerical data vector representation and using a probability distribution function model that models a likelihood of occurrence of the observed user-agent based on patterns learned from historic payload data (e.g., a Gaussian Mixture Model). The predictive score may be compared to a threshold and, based on the comparison, it may be determined whether the user-agent is fraudulent.

Abstract: Systems and methods for emulator detection are disclosed. In one embodiment, a user agent string may be embedded into a first numerical data vector representation. Hardware characteristics of a client device corresponding to the user agent may be embedded into a second numerical data vector representation. Based on the first numerical data vector representation of the user agent and the second numerical data vector representation of the hardware characteristics, and their consistency, the client device may be determined to be an emulator or a non-emulator device.

Abstract: Systems and methods for emulator detection are disclosed. In one embodiment, a user agent string may be embedded into a first numerical data vector representation. Hardware characteristics of a client device corresponding to the user agent may be embedded into a second numerical data vector representation. Based on the first numerical data vector representation of the user agent and the second numerical data vector representation of the hardware characteristics, and their consistency, the client device may be determined to be an emulator or a non-emulator device.

Abstract: Techniques are disclosed relating to transaction authorization. In some embodiments, a server computer system receives and caches browsing information for a device of a user, where the browsing information relates to a transaction service. The server computer system may then receive a request to authorize one or more transactions via the transaction service. The server computer system may evaluate the cached browsing information to determine whether the user is attempting to perform multiple concurrent transactions via the transaction service. Based on the evaluating, the server computer system may determine whether to authorize the one or more transactions. In some embodiments, the disclosed techniques may advantageously prevent or reduce authorization of duplicate transactions that are concurrently attempted by a user.

Abstract: Systems and methods for user-agent anomaly detection are disclosed. In one embodiment, a user-agent string may be embedded into a numerical data vector representation using a sentence embedding algorithm (e.g., FastText). A predictive score may be calculated based on the numerical data vector representation and using a probability distribution function model that models a likelihood of occurrence of the observed user-agent based on patterns learned from historic payload data (e.g., a Gaussian Mixture Model). The predictive score may be compared to a threshold and, based on the comparison, it may be determined whether the user-agent is fraudulent.

Abstract: Techniques are disclosed relating to transaction authorization. In some embodiments, a server computer system receives and caches browsing information for a device of a user, where the browsing information relates to a transaction service. The server computer system may then receive a request to authorize one or more transactions via the transaction service. The server computer system may evaluate the cached browsing information to determine whether the user is attempting to perform multiple concurrent transactions via the transaction service. Based on the evaluating, the server computer system may determine whether to authorize the one or more transactions. In some embodiments, the disclosed techniques may advantageously prevent or reduce authorization of duplicate transactions that are concurrently attempted by a user.