Fixed RemoteIP field parsing in FailedLogonAttempts_UnknownUser.yaml

[0ccupi3R]

The parse operator is incorrectly parsing the events that has more fields after rhost= as given below:

Azure-Sentinel/Solutions/Syslog/Analytic Rules/FailedLogonAttempts_UnknownUser.yaml

Line 29 in 3aee076

| parse SyslogMessage with * "rhost=" RemoteIP

SyslogMessage
------------------------------------------------
pam_sss(sshd:auth): authentication   failure  logname= uid=0 euid=0 tty=ssh   ruser= rhost=10.65.17.140 user=factory
pam_unix(sshd:auth): authentication   failure  logname= uid=0 euid=0 tty=ssh   ruser= rhost=10.65.17.130
pam_sss(sshd:auth): authentication   failure  logname= uid=0 euid=0 tty=ssh   ruser= rhost=10.65.17.122 user=USERID
pam_unix(sshd:auth): authentication   failure  logname= uid=0 euid=0 tty=ssh   ruser= rhost=10.65.17.110
pam_sss(sshd:auth): authentication   failure  logname= uid=0 euid=0 tty=ssh   ruser= rhost=10.65.17.120 user=admin
pam_unix(sshd:auth): authentication   failure  logname= uid=0 euid=0 tty=ssh   ruser= rhost=10.65.17.150

Current Output:

RemoteIP
--------------------------
10.65.17.140 user=factory
10.65.17.130
10.65.17.122 user=USERID
10.65.17.110
10.65.17.120 user=admin
10.65.17.140

Output After Change (Fixed by using extract function)

RemoteIP
------------
10.65.17.140
10.65.17.130
10.65.17.122
10.65.17.110
10.65.17.120
10.65.17.150

Required items, please complete

Change(s):

• See guidance below

Reason for Change(s):

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Version Updated:

• Required only for Detections/Analytic Rule templates
• See guidance below

Testing Completed:

• See guidance below

Checked that the validations are passing and have addressed any issues that are present:

• See guidance below

Guidance <- remove section before submitting

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Change(s):

• Updated syntax for XYZ.yaml

Reason for Change(s):

• New schema used for XYZ.yaml
• Resolves ISSUE Add Logstash required version to Readme file #1234

Version updated:

• Yes
• Detections/Analytic Rule templates are required to have the version updated

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Checked that the validations are passing and have addressed any issues that are present:

• Yes/No/Need Help

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