The present solution is directed to systems and methods for synchronizing a random seed value among a plurality of multi-core nodes in a cluster of nodes for generating a cookie signature. The cookie signature may be used for protection from SYN flood attacks. A cluster of nodes comprises one master node and one or more other nodes. Each node comprises one master core and one or more other cores. A random number is generated at the master core of the master node. The random number is synchronized across every other core. The random number is used to generated a secret key value that is attached in the encoded initial sequence number of a SYN-ACK packet. If the responding ACK packet does not contain the secret key value, then the ACK packet is dropped.