Signature Detail
Short Name |
TFTP:AUDIT:S2C-UNEXP-ACK |
|---|---|
Severity |
Info |
Recommended |
No |
Category |
TFTP |
Release Date |
2003/04/22 |
Update Number |
1213 |
Supported Platforms |
idp-4.0+, isg-3.0+, j-series-9.5+, mx-9.4+, srx-9.2+, srx-branch-9.4+, vsrx-12.1+ |
TFTP: REPLY: Unexpected ACK
This protocol anomaly is an ACK sent from the TFTP server after a client requested to read a file from the server. Normally, servers do not send ACKs; clients send ACKs in response to DATA messages sent from the server. This can indicate a malicious server or a tunneling attempt.
Extended Description
None
References