Quick glance into who’s who in the zoo for users, capabilities, roles, and what indexes are searchable. Also calls out users with can_delete capabilities. Mileage may vary, please comment if there are any issues! <dashboard version=”1.1″> <label>Splunk Insights – Users and Roles</label> <row> <panel> <title>Number of Roles</title> <single> <title>Click to Expand</title> <search> <query>| rest splunk_server=local […]
1st time connection between servers (FTD CISCO)
Description: This query helps you to see all new connections between servers. Still work in progress and can be extended further. “White-listing” happens through the lookup files. Query: index=nfw “Allow” | rex (?:SrcIP.*\b(?<SrcIP>\d+\.\d+\.\d+\.\d+).*DstIP.*\b(?<DstIP>\d+\.\d+\.\d+\.\d+)) | stats count min(_time) AS earliest max(_time) AS maxtime BY SrcIP, DstIP | where earliest>relative_time(now(), “-1d@d”) AND count<=1 | search DstIP=10.0.0.0/8 AND […]
Detect Credit Card Numbers using Luhn Algorithm
Description Detect if any log file in Splunk contains Credit Card numbers. index=* ((source IN(“*.log”,”*.bak”,”*.txt”, “*.csv”,”/tmp*”,”/temp*”,”c:\tmp*”)) OR (tag=web dest_content=*)) | eval comment=”Match against the simple CC regex to narrow down the events in the lookup” | rex max_match=1 “[\”\s\’\,]{0,1}(?<CCMatch>[\d.\-\s]{11,24})[\”\s\’\,]{0,1}” | where isnotnull(CCMatch) | eval comment=”Apply the LUHN algorithm to see if the CC number […]
Zerologon Detection (CVE-2020-1472)
Primary Search for Local Domain Controller Exploitation by Zerologon index=”<windows_index>” (sourcetype=”<windows_sourcetype_security>” OR source=”windows_source_security”) EventCode=”4742″ OR EventCode=”4624″ AND (src_user=”*anonymous*” OR member_id=”*S-1-0*”) `comment(“This looks for all 4624 and 4742 events under an ‘ANONYMOUS USER’, which are tied to the exploitation of Zerologon”)` | eval local_system=mvindex(upper(split(user,”$”)),0) `comment(“This effectively splits the user field, which when parsed with the TA […]
Groundspeed Violation/Improbable Access
Oftentimes we are required to determine impossible or improbably access events. Typically, this is a relatively simple thing to do in a modern SIEM, however Splunk, without ESS, does not have a “great” way to handle this type of temporal correlation aside from appends or joins back to the original data. I constructed the following […]
CrowdStrike Audit Event Correlation
Summary CrowdStrike creates logs in JSON format and sends 2 different datasets to the same sourcetype; security events from their detection tools and audit events from their management tool. These audit tools contain analyst data about when they mark events as true positive, and withing CrowdStrike these are joined with the security event itself. To […]
Significant Data Ingress/Egress
Generally, one expects a client-server conversation to be greater on the download side rather than more data uploaded. This search can detect greater upload than download over a time period, like a client sending significantly more data than it receives from a server (e.g. data ex-filtration). For the best search results, query on a sourcetype […]
Windows Dashboard showing Who (was) logged on to ?
Dashboard with 3 separate columns which allow you to drill into 3 separate assets to find out who was logged on, when they logged on, and how they logged on. Accounts for remote logins, local logins, and unlocks/reconnects accounted for but not Type 3 (network logons for shared file access etc). Time picker set so […]
Nessus Security Center Dashboard
Description: This dashboard is intended make it easier to search the results from Nessus Security Center. It doesn’t require any additional addons. <form> <label>Nessus Scan Results</label> <fieldset submitButton=”true” autoRun=”false”> <input type=”checkbox” token=”t_severity”> <label>Severity</label> <choice value=”Critical”>Critical</choice> <choice value=”High”>High</choice> <choice value=”Medium”>Medium</choice> <choice value=”Low”>Low</choice> <prefix>(</prefix> <suffix>)</suffix> <initialValue>Critical,High,Medium,Low</initialValue> <valuePrefix>severity.name=</valuePrefix> <delimiter> OR </delimiter> </input> <input type=”multiselect” token=”t_scan_name”> <label>Scan Name</label> <choice […]
Successful Logons to WordPress Admin Area
Ever want more detailed information on authentications to your WordPress Admin Area? This Splunk Query will show detailed information on successful authentications to the wp-admin section of your site: sourcetype=”access_combined” uri=”/wp-admin/admin-ajax.php?_fs_blog_admin=*” | iplocation clientip | stats sparkline latest(_time) as Latest_Date count(status) as count values(status) by uri, Country, Region, City, clientip | convert ctime(Latest_Date) | sort […]
Blocked Firewall Scanning Activity with indicator if Source has been allowed.
This search is still a work in progress, but thought I would go ahead and post it. Currently use OPNsense firewall in my house. The purpose of the search is to identify blocked scanning activity on my firewall that does a 2nd search via a join to add if any src_ip that had been blocked […]
High Level Windows Dashboard
Part 1 – User Logon Activity The following Splunk Dashboard provides a high level view of windows user logon activity. It should be emphasized that the focus of this dashboard is fairly high level, has a time picker (defaulting to 7 days) and shows both successful and failed user logons (table and timechart) as well […]
Successful Logons – Windows
The following is a Splunk query that will display a timechart for all successful logons to windows: source=”WinEventLog:security” EventCode=4624 Logon_Type IN (2,7,10,11) NOT user IN (“DWM-*”, “UMFD-*”) | timechart span=1h count by host Here’s a detailed table showing similar information with greater detail: source=”WinEventLog:security” EventCode=4624 Logon_Type IN (2,7,10,11) NOT user IN (“DWM-*”, “UMFD-*”) | eval […]
Failed Logon Attempts – Windows
The following Splunk query will show a timechart of failed logon attempts per host: source=”WinEventLog:security” EventCode=4625 | timechart span=1h count by host The following Splunk query will show a detailed table of failed logon attempts per host and user with 5 minute chunks/blocks of time, as well as show a sparkline (mini timechart) within the […]
Timechart of the status of an Locked Out Account
This query will show a timechart of the status of an Locked Out Account sourcetype=”WinEventLog:Security” EventCode=4625 AND Status=0xC0000234 | timechart count by user | sort -count
Active Directory Password change attempts
Use the following search to create a stacked barchart of AD Password change attempts: source=”WinEventLog:Security” “EventCode=4723″ src_user!=”*$” src_user!=”_svc_*” | eval daynumber=strftime(_time,”%Y-%m-%d”) | chart count by daynumber, status | eval daynumber = mvindex(split(daynumber,”-“),2)
Find success login after 10 failures with streamstats
If you have the Authentication data model configured you can use the following search to quickly find successful logins after 10 failed attempts! | from datamodel:”Authentication”.”Authentication” | search action=failure or action=success | reverse | streamstats window=0 current=true reset_after=”(action=\”success\”)” count as failure_count by src | where action=”success” and failure_count > 10
Detect Username Guessing Brute Force Attacks
The below will detect a form of brute force which most will miss. Whereas other scripts detect multiple logins against a single account, they fail to detect 4 failed logins against 40 accounts. This first checks for all accounts having an account login failure of 4 or more, it then checks for the quantity of […]
Compare Successful Internal Vs External Connections
This query will display a bar chart of all successful Internal vs External SSH connections. Useful for identifying any spikes in connectivity coming from within your network remit or outside of it. Simply change the CIDR matches to match your required LANs. “sshd” AND “Accepted password” | rex “[a-zA-z]{3}\s\d+\s\d+:\d+:\d+\s[a-zA-Z0-9-.]*\s[a-zA-z]{3}\s\d+\s\d+:\d+:\d+\s(?<hostname>.*)\ssshd\[\d+\]:\sAccepted\spassword\sfor\s(?<username>.*)\sfrom\s(?<sourceip>.*)\sport\s(?<sourceport>.*)\sssh2” | eval network=case(cidrmatch(“192.168.0.0/24″, sourceip),”Internal”, cidrmatch(“10.10.0.0/16″,sourceip),”Internal”, […]
Top Offending SSH Failure by Source IP
This displays a list of failed attempts against each connecting IP. Can be used to detect brute force from a particular source IP. You can then put a block up via ACL or whatever method you chose to mitigate the issue. The NOT clause on the first line ignore all attempts to logon to “invalid […]
