TCP: Options Error SACK in SYN Packet
This protocol anomaly triggers when it detects a SACK specification in a SYN packet. SYN packets should carry only SACKPERM, not SACK itself. It is recommended to drop these packets.
Extended Description
If any TCP/IP datagram contains both a SACK value and the SYN flag, then this constitutes a protocol anomaly. Detection of this condition could indicate a network configuration error. It could also indicate that malicious activity involving injection of malformed IP packets is underway.
References
srx-branch-12.3
srx-19.3
srx-branch-19.3
vsrx3bsd-19.2
srx-branch-19.4
vsrx-19.4
mx-12.3
mx-19.4
vmx-19.4
mx-19.3
vsrx3bsd-19.4
srx-19.4
vsrx-12.3
vmx-19.3
vsrx-19.2
srx-12.3