Abstract: There is provided a method for detecting fraudulent use of monetary credentials during online transactions, comprising: receiving by a computing system, from a client terminal via a network, a request to obtain a digital voucher having a certain monetary equivalent using monetary credentials of a user, determining, a risk of malicious use of the monetary credentials according to an analysis of data denoting the context of the monetary credentials, providing, to the client terminal, a digital unusable voucher, wherein the digital unusable voucher is invalid for performing an online transaction, wherein the digital unusable voucher is structurally similar to a valid voucher that is valid for performing the online transaction, and identifying malicious use of the monetary credentials when within an elapsed predefined interval of time, no appeal in response to invalidity of the digital usable voucher during an attempt to perform the online transaction is received from the user.

Abstract: There is provided a method for detecting fraudulent use of monetary credentials during online transactions, comprising: receiving by a computing system, from a client terminal via a network, a request to obtain a digital voucher having a certain monetary equivalent using monetary credentials of a user, determining, a risk of malicious use of the monetary credentials according to an analysis of data denoting the context of the monetary credentials, providing, to the client terminal, a digital unusable voucher, wherein the digital unusable voucher is invalid for performing an online transaction, wherein the digital unusable voucher is structurally similar to a valid voucher that is valid for performing the online transaction, and identifying malicious use of the monetary credentials when within an elapsed predefined interval of time, no appeal in response to invalidity of the digital usable voucher during an attempt to perform the online transaction is received from the user.

Abstract: There is provided a method, comprising: receiving a serial code and an associated value, accessing a first database storing active serial codes each associated with an active value, wherein the first database is accessed for each received serial code when the serial code is active and when the serial code is inactive, and the first database is accessed for each received serial code when the associated value is active and when the associated value is inactive, when no match is found, accessing a second database storing invalid serial codes each associated with an invalid value, matching the received serial code to a certain invalid serial code, and providing the invalid value associated with the certain invalid serial code, wherein a client terminal is unable to distinguish between the provided invalid value and an active value otherwise returned for a positive match between the serial code and the active serial codes.

Abstract: There is provided a method, comprising: receiving a serial code and an associated value, accessing a first database storing active serial codes each associated with an active value, wherein the first database is accessed for each received serial code when the serial code is active and when the serial code is inactive, and the first database is accessed for each received serial code when the associated value is active and when the associated value is inactive, when no match is found, accessing a second database storing invalid serial codes each associated with an invalid value, matching the received serial code to a certain invalid serial code, and providing the invalid value associated with the certain invalid serial code, wherein a client terminal is unable to distinguish between the provided invalid value and an active value otherwise returned for a positive match between the serial code and the active serial codes.

Abstract: There is provided a method for detecting fraudulent use of monetary credentials during online transactions, comprising: receiving by a computing system, from a client terminal via a network, a request to obtain a digital voucher having a certain monetary equivalent using monetary credentials of a user, determining, a risk of malicious use of the monetary credentials according to an analysis of data denoting the context of the monetary credentials, providing, to the client terminal, a digital unusable voucher, wherein the digital unusable voucher is invalid for performing an online transaction, wherein the digital unusable voucher is structurally similar to a valid voucher that is valid for performing the online transaction, and identifying malicious use of the monetary credentials when within an elapsed predefined interval of time, no appeal in response to invalidity of the digital usable voucher during an attempt to perform the online transaction is received from the user.

Abstract: There is provided a method for location based purchase of merchant credit vouchers, comprising: gathering merchant credit vouchers from sellers; mapping each respective merchant credit voucher to at least one geographical redeeming area; receiving a geographical location of a user; matching the user geographical location to a certain geographical redeeming area from the geographical redeeming areas to identify a group of merchant credit vouchers redeemable with at least one merchant located within the geographical redeeming area of the user; receiving a purchase order for purchase of at least one of the merchant credit vouchers from the group; transmitting a digital representation of the purchased merchant credit voucher to the mobile client terminal for payment by the user at the merchant; and crediting an account of the user and debiting an account of a seller of the purchased at least one merchant credit voucher after the transmission of the digital representation.