# ASP_SFW_TCP_BAD_SYN_COOKIE_RESP

## Canonical Reference

[ASP_SFW_TCP_BAD_SYN_COOKIE_RESP](https://apps.juniper.net/syslog-explorer/?msg=ASP_SFW_TCP_BAD_SYN_COOKIE_RESP)

**Canonical URL:**  
https://apps.juniper.net/syslog-explorer/?msg=ASP_SFW_TCP_BAD_SYN_COOKIE_RESP

## SYSLOG Details
- **Message**: <variable>syslog-prefix</variable> <variable>error-code</variable>: proto <variable>protocol-id</variable> (<variable>protocol-name</variable>), <variable>source-interface-name</variable><variable>separator</variable><variable>source-address</variable>:<variable>source-port</variable> -> <variable>destination-address</variable><variable>destination-port</variable>, <variable>event-type</variable>
- **Help**: Stateful firewall discarded suspicious ACK packet
- **Description**: The stateful firewall discarded the Transmission Control Protocol (TCP) ACK packet with the indicated characteristics, either because it is the first packet in a session, or because its sequence number did not match the sequence number in the SYN/ACK packet that the firewall previously generated for the session. The firewall generates SYN/ACK packets when SYN cookie protection is activated. The discarded packet contained the indicated information about its protocol (numerical identifier and name), source (logical interface name, IP address, and port number), and destination (IP address and port number).
- **Type**: Event: This message reports an event, not an error
- **Severity**: notice
- **Cause**: -
- **Action**: -
- **Attributes**: syslog-prefix
error-code
protocol-id
protocol-name
source-interface-name
separator
source-address
source-port
destination-address
destination-port
event-type
- **Facility**: LOG_PFE

## Found this message in the following releases:
- [Junos OS 26.2R1](https://apps.juniper.net/syslog-explorer/?msg=ASP_SFW_TCP_BAD_SYN_COOKIE_RESP&sw=Junos%20OS&rel=26.2R1)
- [Junos OS 25.4R1](https://apps.juniper.net/syslog-explorer/?msg=ASP_SFW_TCP_BAD_SYN_COOKIE_RESP&sw=Junos%20OS&rel=25.4R1)
- [Junos OS 25.2R2](https://apps.juniper.net/syslog-explorer/?msg=ASP_SFW_TCP_BAD_SYN_COOKIE_RESP&sw=Junos%20OS&rel=25.2R2)
- [Junos OS 25.2R1](https://apps.juniper.net/syslog-explorer/?msg=ASP_SFW_TCP_BAD_SYN_COOKIE_RESP&sw=Junos%20OS&rel=25.2R1)
- [Junos OS 24.4R2](https://apps.juniper.net/syslog-explorer/?msg=ASP_SFW_TCP_BAD_SYN_COOKIE_RESP&sw=Junos%20OS&rel=24.4R2)
- [Junos OS 24.4R1](https://apps.juniper.net/syslog-explorer/?msg=ASP_SFW_TCP_BAD_SYN_COOKIE_RESP&sw=Junos%20OS&rel=24.4R1)
- [Junos OS 24.2R2](https://apps.juniper.net/syslog-explorer/?msg=ASP_SFW_TCP_BAD_SYN_COOKIE_RESP&sw=Junos%20OS&rel=24.2R2)
- [Junos OS 24.2R1](https://apps.juniper.net/syslog-explorer/?msg=ASP_SFW_TCP_BAD_SYN_COOKIE_RESP&sw=Junos%20OS&rel=24.2R1)
- [Junos OS 23.4R2](https://apps.juniper.net/syslog-explorer/?msg=ASP_SFW_TCP_BAD_SYN_COOKIE_RESP&sw=Junos%20OS&rel=23.4R2)
- [Junos OS 23.4R1](https://apps.juniper.net/syslog-explorer/?msg=ASP_SFW_TCP_BAD_SYN_COOKIE_RESP&sw=Junos%20OS&rel=23.4R1)
- [Junos OS 23.2R2](https://apps.juniper.net/syslog-explorer/?msg=ASP_SFW_TCP_BAD_SYN_COOKIE_RESP&sw=Junos%20OS&rel=23.2R2)
- [Junos OS 23.2R1](https://apps.juniper.net/syslog-explorer/?msg=ASP_SFW_TCP_BAD_SYN_COOKIE_RESP&sw=Junos%20OS&rel=23.2R1)
- [Junos OS 22.4R3](https://apps.juniper.net/syslog-explorer/?msg=ASP_SFW_TCP_BAD_SYN_COOKIE_RESP&sw=Junos%20OS&rel=22.4R3)
- [Junos OS 22.4R2](https://apps.juniper.net/syslog-explorer/?msg=ASP_SFW_TCP_BAD_SYN_COOKIE_RESP&sw=Junos%20OS&rel=22.4R2)
- [Junos OS 22.4R1](https://apps.juniper.net/syslog-explorer/?msg=ASP_SFW_TCP_BAD_SYN_COOKIE_RESP&sw=Junos%20OS&rel=22.4R1)
- [Junos OS 22.2R3](https://apps.juniper.net/syslog-explorer/?msg=ASP_SFW_TCP_BAD_SYN_COOKIE_RESP&sw=Junos%20OS&rel=22.2R3)
- [Junos OS 22.2R2](https://apps.juniper.net/syslog-explorer/?msg=ASP_SFW_TCP_BAD_SYN_COOKIE_RESP&sw=Junos%20OS&rel=22.2R2)
- [Junos OS 22.2R1](https://apps.juniper.net/syslog-explorer/?msg=ASP_SFW_TCP_BAD_SYN_COOKIE_RESP&sw=Junos%20OS&rel=22.2R1)