SYSLOG: Unexpected Reply
This protocol anomaly triggers when it detects a SYSLOG server reply. The SYSLOG protocol is a one-way protocol (client to the server) and the server should not send replies. This can indicate tunneling over the SYSLOG protocol.
Extended Description
The presence of this packet could indicate a software misconfiguration or that a remote attacker is attempting to tunnel over UDP port 514 to bypass firewall rules.
References
Short Name
SYSLOG:FAILURES:UNEXP-REPLY
Severity
Major
Recommended
False
Recommended Action
None
Category
SYSLOG
Release Date
08/27/2003
Supported Platforms
mx-19.3
vmx-19.3
vsrx-19.2
srx-19.3
srx-branch-19.3
vsrx3bsd-19.2
srx-19.4
vsrx3bsd-19.4
srx-branch-19.4
vsrx-19.4
vmx-19.4
mx-19.4
srxevo-25.4
vsrx-26.2
srx-26.2
srx-branch-26.2
vsrx3bsd-26.2
mx-12.3
srx-12.3
srx-branch-12.3
vsrx-12.3
Sigpack Version
3324
False Positive
Unknown