SSH and SSHD checksum alerts

[Pizzicato]

Hi,
I'm receiving this mails every now and then:

Trigger: /usr/bin/ssh has been changed on server Master
Trigger status: PROBLEM
Trigger severity: Average
Trigger URL: 

Item values:

1. Checksum of /usr/bin/ssh (Master:vfs.file.cksum[/usr/bin/ssh]):

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