Logcheck currently sends lots of emails with messages like this
Jun 6 19:31:44 <hostname> kernel: [UFW BLOCK] IN=eth0 OUT= MAC=<mac-address> SRC=<source-ip> DST=<destination-ip> LEN=40 TOS=0x00 PREC=0x00 TTL=116 ID=28729 DF PROTO=TCP SPT=56681 DPT=80 WINDOW=16652 RES=0x00 ACK FIN URGP=0
According to this Q&A this packet is blocked because it is optional.
Is it reasonable to have the following /etc/logcheck/ignore.d.server/ufw
^\w{3} [ :[:digit:]]{11} [._[:alnum:]-]+ kernel: \[UFW BLOCK\].*ACK FIN.*