Merge pull request #2979 from nterl0k/nterl0k-T1110.003-NTLM-bruteforce

Nterl0k - T1110.003 NTLM Bruteforce
This commit is contained in:
Bhavin Patel
2024-08-05 17:51:18 -07:00
committed by GitHub
6 changed files with 318 additions and 0 deletions
@@ -0,0 +1,63 @@
name: Windows Multiple NTLM Null Domain Authentications
id: c187ce2c-c88e-4cec-8a1c-607ca0dedd78
version: 1
date: '2024-03-16'
author: Steven Dick
status: production
type: TTP
description: The following analytic detects when a device is the target of numerous NTLM authentications using a null domain. This activity generally results when an attacker attempts to brute force, password spray, or otherwise authenticate to a domain joined Windows device from a non-domain device. This activity may also generate a large number of EventID 4776 events in tandem, however these events will not indicate the attacker or target device
data_source:
- NTLM Operational 8004,8005,8006
search: '`ntlm_audit` EventCode IN (8004,8005,8006) DomainName=NULL UserName!=NULL
| eval src = replace(WorkstationName,"\\\\","") ```CIM alignment, remove leading \\ from some auth attempts ```
| eval dest = SChannelName, user = UserName ``` CIM alignment```
| where SChannelName!=src ``` Remove NTLM auths to self, improves accuracy for certain applications```
| `windows_multiple_ntlm_null_domain_authentications_filter`
| stats count min(_time) as firstTime max(_time) as lastTime dc(eval(upper(user))) as unique_count dc(eval(upper(src))) as src_count by dest
| eventstats avg(unique_count) as unique_avg , stdev(unique_count) as unique_std
| eval upperBound_unique=(1+unique_avg+unique_std*3) ``` adjust formula for sensitivity```
| eval isOutlier=CASE(unique_count > upperBound_unique, 1, true(), 0)
| where isOutlier==1
| `security_content_ctime(firstTime)`
| `security_content_ctime(lastTime)`'
how_to_implement: The following analytic requires that NTLM Operational logs to be imported from the environment Domain Controllers. This requires configuration of specific auditing settings, see Microsoft references for further guidance. This analytic is specific to EventID 8004~8006.
known_false_positives: Applications that deal with non-domain joined authentications. Recommend adjusting the upperBound_unique eval for tailoring the correlation to your environment, running with a 24hr search window will smooth out some statistical noise.
references:
- https://attack.mitre.org/techniques/T1110/003/
- https://techcommunity.microsoft.com/t5/ask-the-directory-services-team/ntlm-blocking-and-you-application-analysis-and-auditing/ba-p/397191
- https://techcommunity.microsoft.com/t5/microsoft-defender-for-identity/enriched-ntlm-authentication-data-using-windows-event-8004/m-p/871827
- https://www.varonis.com/blog/investigate-ntlm-brute-force
- https://learn.microsoft.com/en-us/openspecs/windows_protocols/ms-nrpc/4d1235e3-2c96-4e9f-a147-3cb338a0d09f
tags:
analytic_story:
- Active Directory Password Spraying
asset_type: Endpoint
confidence: 100
impact: 75
message: The device [$dest$] was the target of $count$ NTLM authentications from $src_count$ sources using $unique_count$ unique user accounts.
mitre_attack_id:
- T1110
- T1110.003
observable:
- name: dest
type: Hostname
role:
- Victim
product:
- Splunk Enterprise
- Splunk Enterprise Security
- Splunk Cloud
required_fields:
- _time
- EventCode
- DomainName
- Security
- WorkstationName
risk_score: 50
security_domain: endpoint
tests:
- name: True Positive Test
attack_data:
- data: https://media.githubusercontent.com/media/splunk/attack_data/master/datasets/attack_techniques/T1110.003/ntlm_bruteforce/ntlm_bruteforce.log
source: XmlWinEventLog:Microsoft-Windows-NTLM/Operational
sourcetype: XmlWinEventLog
@@ -0,0 +1,63 @@
name: Windows Unusual NTLM Authentication Destinations By Source
id: ae9b0df5-5fb0-477f-abc9-47faf42aa91d
version: 1
date: '2024-03-16'
author: Steven Dick
status: production
type: Anomaly
description: The following analytic detects when an unusual number NTLM authentications is attempted by the same source against multiple destinations. This activity generally results when an attacker attempts to brute force, password spray, or otherwise authenticate to a multiple domain joined Windows devices using an NTLM based process/attack. This same activity may also generate a large number of EventID 4776 events as well.
data_source:
- NTLM Operational 8004,8005,8006
search: '`ntlm_audit` EventCode = 8004 SChannelName=* WorkstationName=*
| eval src = replace(WorkstationName,"\\\\","") ```CIM alignment, remove leading \\ from some auth attempts ```
| eval dest = SChannelName, user = UserName ``` CIM alignment```
| where SChannelName!=src ``` Remove NTLM auths to self, improves accuracy for certain applications ```
| `windows_unusual_ntlm_authentication_destinations_by_source_filter`
| stats count min(_time) as firstTime max(_time) as lastTime dc(eval(upper(dest))) as unique_count by src
| eventstats avg(unique_count) as unique_avg , stdev(unique_count) as unique_std
| eval upperBound_unique=(1+unique_avg+unique_std*3) ``` adjust formula for sensitivity```
| eval isOutlier=CASE(unique_count > upperBound_unique, 1, true(), 0)
| where isOutlier==1
| `security_content_ctime(firstTime)`
| `security_content_ctime(lastTime)`'
how_to_implement: The following analytic requires that NTLM Operational logs to be imported from the environment Domain Controllers. This requires configuration of specific auditing settings, see Microsoft references for further guidance. This analytic is specific to EventID 8004~8006.
known_false_positives: Vulnerability scanners, print servers, and applications that deal with non-domain joined authentications. Recommend adjusting the upperBound_unique eval for tailoring the correlation to your environment, running with a 24hr search window will smooth out some statistical noise.
references:
- https://attack.mitre.org/techniques/T1110/003/
- https://techcommunity.microsoft.com/t5/ask-the-directory-services-team/ntlm-blocking-and-you-application-analysis-and-auditing/ba-p/397191
- https://techcommunity.microsoft.com/t5/microsoft-defender-for-identity/enriched-ntlm-authentication-data-using-windows-event-8004/m-p/871827
- https://www.varonis.com/blog/investigate-ntlm-brute-force
- https://learn.microsoft.com/en-us/openspecs/windows_protocols/ms-nrpc/4d1235e3-2c96-4e9f-a147-3cb338a0d09f
tags:
analytic_story:
- Active Directory Password Spraying
asset_type: Endpoint
confidence: 100
impact: 25
message: The device [$src$] attempted $count$ NTLM authentications against $unique_count$ destinations.
mitre_attack_id:
- T1110
- T1110.003
observable:
- name: src
type: Hostname
role:
- Victim
product:
- Splunk Enterprise
- Splunk Enterprise Security
- Splunk Cloud
required_fields:
- _time
- EventCode
- DomainName
- Security
- WorkstationName
risk_score: 25
security_domain: endpoint
tests:
- name: True Positive Test
attack_data:
- data: https://media.githubusercontent.com/media/splunk/attack_data/master/datasets/attack_techniques/T1110.003/ntlm_bruteforce/ntlm_bruteforce.log
source: XmlWinEventLog:Microsoft-Windows-NTLM/Operational
sourcetype: XmlWinEventLog
@@ -0,0 +1,63 @@
name: Windows Unusual NTLM Authentication Destinations By User
id: a4d86702-402b-4a4f-8d06-9d61e6c39cad
version: 1
date: '2024-03-16'
author: Steven Dick
status: production
type: Anomaly
description: The following analytic detects when an unusual number of NTLM authentications is attempted by the same user account against multiple destinations. This activity generally results when an attacker attempts to brute force, password spray, or otherwise authenticate to numerous domain joined Windows devices using an NTLM based process/attack. This same activity may also generate a large number of EventID 4776 events as well.
data_source:
- NTLM Operational 8004,8005,8006
search: '`ntlm_audit` EventCode = 8004 SChannelName=* WorkstationName=*
| eval src = replace(WorkstationName,"\\\\","") ```CIM alignment, remove leading \\ from some auth attempts ```
| eval dest = SChannelName, user = UserName ``` CIM alignment```
| where SChannelName!=src ``` Remove NTLM auths to self, improves accuracy for certain applications ```
| `windows_unusual_ntlm_authentication_destinations_by_user_filter`
| stats count min(_time) as firstTime max(_time) as lastTime dc(eval(upper(dest))) as unique_count by user
| eventstats avg(unique_count) as unique_avg , stdev(unique_count) as unique_std
| eval upperBound_unique=(1+unique_avg+unique_std*3) ``` adjust formula for sensitivity```
| eval isOutlier=CASE(unique_count > upperBound_unique, 1, true(), 0)
| where isOutlier==1
| `security_content_ctime(firstTime)`
| `security_content_ctime(lastTime)`'
how_to_implement: The following analytic requires that NTLM Operational logs to be imported from the environment Domain Controllers. This requires configuration of specific auditing settings, see Microsoft references for further guidance. This analytic is specific to EventID 8004~8006.
known_false_positives: Vulnerability scanners, print servers, and applications that deal with non-domain joined authentications. Recommend adjusting the upperBound_unique eval for tailoring the correlation to your environment, running with a 24hr search window will smooth out some statistical noise.
references:
- https://attack.mitre.org/techniques/T1110/003/
- https://techcommunity.microsoft.com/t5/ask-the-directory-services-team/ntlm-blocking-and-you-application-analysis-and-auditing/ba-p/397191
- https://techcommunity.microsoft.com/t5/microsoft-defender-for-identity/enriched-ntlm-authentication-data-using-windows-event-8004/m-p/871827
- https://www.varonis.com/blog/investigate-ntlm-brute-force
- https://learn.microsoft.com/en-us/openspecs/windows_protocols/ms-nrpc/4d1235e3-2c96-4e9f-a147-3cb338a0d09f
tags:
analytic_story:
- Active Directory Password Spraying
asset_type: Endpoint
confidence: 100
impact: 25
message: The user [$user$] attempted $count$ NTLM authentications against $unique_count$ destinations.
mitre_attack_id:
- T1110
- T1110.003
observable:
- name: user
type: User
role:
- Victim
product:
- Splunk Enterprise
- Splunk Enterprise Security
- Splunk Cloud
required_fields:
- _time
- EventCode
- DomainName
- Security
- WorkstationName
risk_score: 25
security_domain: endpoint
tests:
- name: True Positive Test
attack_data:
- data: https://media.githubusercontent.com/media/splunk/attack_data/master/datasets/attack_techniques/T1110.003/ntlm_bruteforce/ntlm_bruteforce.log
source: XmlWinEventLog:Microsoft-Windows-NTLM/Operational
sourcetype: XmlWinEventLog
@@ -0,0 +1,63 @@
name: Windows Unusual NTLM Authentication Users By Destination
id: 1120a204-8444-428b-8657-6ea4e1f3e840
version: 1
date: '2024-03-16'
author: Steven Dick
status: production
type: Anomaly
description: The following analytic detects when a device is the target of numerous NTLM authentications using a null domain. This activity generally results when an attacker attempts to brute force, password spray, or otherwise authenticate to a domain joined Windows device from a non-domain device. This activity may also generate a large number of EventID 4776 events in tandem, however these events will not indicate the attacker or target device.
data_source:
- NTLM Operational 8004,8005,8006
search: '`ntlm_audit` EventCode = 8004 SChannelName=* WorkstationName=*
| eval src = replace(WorkstationName,"\\\\","") ```CIM alignment, remove leading \\ from some auth attempts ```
| eval dest = SChannelName, user = UserName ``` CIM alignment```
| where SChannelName!=src ``` Remove NTLM auths to self, improves accuracy for certain applications ```
| `windows_unusual_ntlm_authentication_users_by_destination_filter`
| stats count min(_time) as firstTime max(_time) as lastTime dc(eval(upper(user))) as unique_count by dest
| eventstats avg(unique_count) as unique_avg , stdev(unique_count) as unique_std
| eval upperBound_unique=(1+unique_avg+unique_std*3) ``` adjust formula for sensitivity```
| eval isOutlier=CASE(unique_count > upperBound_unique, 1, true(), 0)
| where isOutlier==1
| `security_content_ctime(firstTime)`
| `security_content_ctime(lastTime)`'
how_to_implement: The following analytic detects when an unusual number of NTLM authentications is attempted against the same destination. This activity generally results when an attacker attempts to brute force, password spray, or otherwise authenticate to a domain joined Windows device using an NTLM based process/attack. This same activity may also generate a large number of EventID 4776 events as well.
known_false_positives: Vulnerability scanners, print servers, and applications that deal with non-domain joined authentications. Recommend adjusting the upperBound_unique eval for tailoring the correlation to your environment, running with a 24hr search window will smooth out some statistical noise.
references:
- https://attack.mitre.org/techniques/T1110/003/
- https://techcommunity.microsoft.com/t5/ask-the-directory-services-team/ntlm-blocking-and-you-application-analysis-and-auditing/ba-p/397191
- https://techcommunity.microsoft.com/t5/microsoft-defender-for-identity/enriched-ntlm-authentication-data-using-windows-event-8004/m-p/871827
- https://www.varonis.com/blog/investigate-ntlm-brute-force
- https://learn.microsoft.com/en-us/openspecs/windows_protocols/ms-nrpc/4d1235e3-2c96-4e9f-a147-3cb338a0d09f
tags:
analytic_story:
- Active Directory Password Spraying
asset_type: Endpoint
confidence: 100
impact: 25
message: The device [$dest$] was the target of $count$ NTLM authentications using $unique_count$ unique user accounts.
mitre_attack_id:
- T1110
- T1110.003
observable:
- name: dest
type: Hostname
role:
- Victim
product:
- Splunk Enterprise
- Splunk Enterprise Security
- Splunk Cloud
required_fields:
- _time
- EventCode
- DomainName
- Security
- WorkstationName
risk_score: 25
security_domain: endpoint
tests:
- name: True Positive Test
attack_data:
- data: https://media.githubusercontent.com/media/splunk/attack_data/master/datasets/attack_techniques/T1110.003/ntlm_bruteforce/ntlm_bruteforce.log
source: XmlWinEventLog:Microsoft-Windows-NTLM/Operational
sourcetype: XmlWinEventLog
@@ -0,0 +1,63 @@
name: Windows Unusual NTLM Authentication Users By Source
id: 80fcc4d4-fd90-488e-b55a-4e7190ae6ce2
version: 1
date: '2024-03-16'
author: Steven Dick
status: production
type: Anomaly
description: The following analytic detects when an unusual number of NTLM authentications is attempted by the same source. This activity generally results when an attacker attempts to brute force, password spray, or otherwise authenticate to a domain joined Windows device using an NTLM based process/attack. This same activity may also generate a large number of EventID 4776 events in as well.
data_source:
- NTLM Operational 8004,8005,8006
search: '`ntlm_audit` EventCode = 8004 SChannelName=* WorkstationName=*
| eval src = replace(WorkstationName,"\\\\","") ```CIM alignment, remove leading \\ from some auth attempts ```
| eval dest = SChannelName, user = UserName ``` CIM alignment```
| where SChannelName!=src ``` Remove NTLM auths to self, improves accuracy for certain applications ```
| `windows_unusual_ntlm_authentication_users_by_source_filter`
| stats count min(_time) as firstTime max(_time) as lastTime dc(eval(upper(user))) as unique_count by src
| eventstats avg(unique_count) as unique_avg , stdev(unique_count) as unique_std
| eval upperBound_unique=(1+unique_avg+unique_std*3) ``` adjust formula for sensitivity```
| eval isOutlier=CASE(unique_count > upperBound_unique, 1, true(), 0)
| where isOutlier==1
| `security_content_ctime(firstTime)`
| `security_content_ctime(lastTime)`'
how_to_implement: The following analytic requires that NTLM Operational logs to be imported from the environment Domain Controllers. This requires configuration of specific auditing settings, see Microsoft references for further guidance. This analytic is specific to EventID 8004~8006.
known_false_positives: Vulnerability scanners, print servers, and applications that deal with non-domain joined authentications. Recommend adjusting the upperBound_unique eval for tailoring the correlation to your environment, running with a 24hr search window will smooth out some statistical noise.
references:
- https://attack.mitre.org/techniques/T1110/003/
- https://techcommunity.microsoft.com/t5/ask-the-directory-services-team/ntlm-blocking-and-you-application-analysis-and-auditing/ba-p/397191
- https://techcommunity.microsoft.com/t5/microsoft-defender-for-identity/enriched-ntlm-authentication-data-using-windows-event-8004/m-p/871827
- https://www.varonis.com/blog/investigate-ntlm-brute-force
- https://learn.microsoft.com/en-us/openspecs/windows_protocols/ms-nrpc/4d1235e3-2c96-4e9f-a147-3cb338a0d09f
tags:
analytic_story:
- Active Directory Password Spraying
asset_type: Endpoint
confidence: 100
impact: 25
message: The device [$src$] attempted $count$ NTLM authentications using $unique_count$ user accounts.
mitre_attack_id:
- T1110
- T1110.003
observable:
- name: src
type: Hostname
role:
- Victim
product:
- Splunk Enterprise
- Splunk Enterprise Security
- Splunk Cloud
required_fields:
- _time
- EventCode
- DomainName
- Security
- WorkstationName
risk_score: 25
security_domain: endpoint
tests:
- name: True Positive Test
attack_data:
- data: https://media.githubusercontent.com/media/splunk/attack_data/master/datasets/attack_techniques/T1110.003/ntlm_bruteforce/ntlm_bruteforce.log
source: XmlWinEventLog:Microsoft-Windows-NTLM/Operational
sourcetype: XmlWinEventLog
+3
View File
@@ -0,0 +1,3 @@
definition: sourcetype=XmlWinEventLog:Microsoft-Windows-NTLM/Operational OR source=XmlWinEventLog:Microsoft-Windows-NTLM/Operational
description: Customer specific splunk configurations(eg- index, source, sourcetype). Replace the macro definition with configurations for your Splunk Environmnent.
name: ntlm_audit