The present invention concerns a method for processing messages intended to allow the access to conditional access content and to a security module arranged for implementing this method. The method comprises the steps of receiving by a security module comprising at least one decryption module, a plurality of messages, these messages belonging to at least two different categories; assigning a different priority level to messages from each different category, one of said priority level being defined as high and another priority level, lower that the high priority level, being defined as the standard priority level; associating a value to the messages to which the standard priority level has been assigned; assigning at least one threshold value for the value associated with messages having a standard priority level; and comparing between the threshold value for a determined message and the value associated with said message. If no value associated with said message having standard priority level exceeds the corresponding threshold value, processing the messages according to their priority level, a message to which the high priority level has been assigned being processed before a message to which a lower priority level has been assigned, and change of the value associated with the messages having a standard priority level according to said predefined rule. If the value associated with one of said messages having a standard priority level exceeds the threshold value for the corresponding message, processing one of the messages having a standard priority level before processing a message having a higher priority level, and change of the value associated with the messages having a standard priority level according to said predefined rule.