Detect instances of multiple client errors occurring within a brief period of time ASIM Web Session
Id | faa40333-1e8b-40cc-a003-51ae41fa886f |
Rulename | Detect instances of multiple client errors occurring within a brief period of time (ASIM Web Session) |
Description | This detection mechanism identifies situations where multiple client errors originate from a single source within a limited time frame. |
Severity | Medium |
Tactics | InitialAccess CommandAndControl |
Techniques | T1190 T1133 T1071 |
Kind | Scheduled |
Query frequency | 1h |
Query period | 1h |
Trigger threshold | 0 |
Trigger operator | gt |
Source Uri | https://github.com/Azure/Azure-Sentinel/blob/master/Solutions/Web Session Essentials/Analytic Rules/MultipleClientErrorsWithinShortTime.yaml |
Version | 1.0.0 |
Arm template | faa40333-1e8b-40cc-a003-51ae41fa886f.json |
// HTTP response status codes indicate whether a specific HTTP request has been successfully completed.
// Please refer this for more details: https://developer.mozilla.org/en-US/docs/Web/HTTP/Status
let threshold = 100; // You can set threshold value that suits your environment
_Im_WebSession(starttime=ago(1h))
| where toint(EventResultDetails) between (400 .. 499)
| summarize
TotalErrorCount = count(),
EventStartTime = min(TimeGenerated),
EventEndTime = max(TimeGenerated),
URLs=make_set(Url, 100),
EventResultDetailsSet=make_set(EventResultDetails,10)
by SrcIpAddr, bin(TimeGenerated, 5m), SrcUsername, SrcHostname
| where TotalErrorCount > threshold
| extend Name = iif(SrcUsername contains "@", tostring(split(SrcUsername,'@',0)[0]),SrcUsername), UPNSuffix = iif(SrcUsername contains "@",tostring(split(SrcUsername,'@',1)[0]),""), Threshold=threshold
name: Detect instances of multiple client errors occurring within a brief period of time (ASIM Web Session)
relevantTechniques:
- T1190
- T1133
- T1071
severity: Medium
queryFrequency: 1h
triggerOperator: gt
customDetails:
TotalErrorCount: TotalErrorCount
EventEndTime: EventEndTime
RequestURLs: URLs
ErrorThreshold: Threshold
EventResultSet: EventResultDetailsSet
EventStartTime: EventStartTime
tags:
- Schema: WebSession
SchemaVersion: 0.2.6
status: Available
description: |
'This detection mechanism identifies situations where multiple client errors originate from a single source within a limited time frame.'
OriginalUri: https://github.com/Azure/Azure-Sentinel/blob/master/Solutions/Web Session Essentials/Analytic Rules/MultipleClientErrorsWithinShortTime.yaml
alertDetailsOverride:
alertDisplayNameFormat: High number of client errors originated by user '{{SrcUsername}}' from IP address '{{SrcIpAddr}}'
alertDescriptionFormat: "The client has made a total of '{{TotalErrorCount}}' requests to URLs '{{URLs}}', which have resulted in client errors. A sudden surge in HTTP code errors, especially in the form of client-side errors like 400 or 401, could indicate malicious activity, such as attackers attempting to exploit vulnerabilities or perform unauthorized actions. For detailed information regarding the specific errors encountered, please refer to the following link: https://developer.mozilla.org/en-US/docs/Web/HTTP/Status."
requiredDataConnectors: []
entityMappings:
- fieldMappings:
- identifier: Address
columnName: SrcIpAddr
entityType: IP
- fieldMappings:
- identifier: Name
columnName: Name
- identifier: UPNSuffix
columnName: UPNSuffix
entityType: Account
- fieldMappings:
- identifier: HostName
columnName: SrcHostname
entityType: Host
tactics:
- InitialAccess
- CommandAndControl
queryPeriod: 1h
query: |
// HTTP response status codes indicate whether a specific HTTP request has been successfully completed.
// Please refer this for more details: https://developer.mozilla.org/en-US/docs/Web/HTTP/Status
let threshold = 100; // You can set threshold value that suits your environment
_Im_WebSession(starttime=ago(1h))
| where toint(EventResultDetails) between (400 .. 499)
| summarize
TotalErrorCount = count(),
EventStartTime = min(TimeGenerated),
EventEndTime = max(TimeGenerated),
URLs=make_set(Url, 100),
EventResultDetailsSet=make_set(EventResultDetails,10)
by SrcIpAddr, bin(TimeGenerated, 5m), SrcUsername, SrcHostname
| where TotalErrorCount > threshold
| extend Name = iif(SrcUsername contains "@", tostring(split(SrcUsername,'@',0)[0]),SrcUsername), UPNSuffix = iif(SrcUsername contains "@",tostring(split(SrcUsername,'@',1)[0]),""), Threshold=threshold
version: 1.0.0
kind: Scheduled
eventGroupingSettings:
aggregationKind: AlertPerResult
triggerThreshold: 0
id: faa40333-1e8b-40cc-a003-51ae41fa886f
{
"$schema": "https://schema.management.azure.com/schemas/2019-04-01/deploymentTemplate.json#",
"contentVersion": "1.0.0.0",
"parameters": {
"workspace": {
"type": "String"
}
},
"resources": [
{
"apiVersion": "2024-01-01-preview",
"id": "[concat(resourceId('Microsoft.OperationalInsights/workspaces/providers', parameters('workspace'), 'Microsoft.SecurityInsights'),'/alertRules/faa40333-1e8b-40cc-a003-51ae41fa886f')]",
"kind": "Scheduled",
"name": "[concat(parameters('workspace'),'/Microsoft.SecurityInsights/faa40333-1e8b-40cc-a003-51ae41fa886f')]",
"properties": {
"alertDetailsOverride": {
"alertDescriptionFormat": "The client has made a total of '{{TotalErrorCount}}' requests to URLs '{{URLs}}', which have resulted in client errors. A sudden surge in HTTP code errors, especially in the form of client-side errors like 400 or 401, could indicate malicious activity, such as attackers attempting to exploit vulnerabilities or perform unauthorized actions. For detailed information regarding the specific errors encountered, please refer to the following link: https://developer.mozilla.org/en-US/docs/Web/HTTP/Status.",
"alertDisplayNameFormat": "High number of client errors originated by user '{{SrcUsername}}' from IP address '{{SrcIpAddr}}'"
},
"alertRuleTemplateName": "faa40333-1e8b-40cc-a003-51ae41fa886f",
"customDetails": {
"ErrorThreshold": "Threshold",
"EventEndTime": "EventEndTime",
"EventResultSet": "EventResultDetailsSet",
"EventStartTime": "EventStartTime",
"RequestURLs": "URLs",
"TotalErrorCount": "TotalErrorCount"
},
"description": "'This detection mechanism identifies situations where multiple client errors originate from a single source within a limited time frame.'\n",
"displayName": "Detect instances of multiple client errors occurring within a brief period of time (ASIM Web Session)",
"enabled": true,
"entityMappings": [
{
"entityType": "IP",
"fieldMappings": [
{
"columnName": "SrcIpAddr",
"identifier": "Address"
}
]
},
{
"entityType": "Account",
"fieldMappings": [
{
"columnName": "Name",
"identifier": "Name"
},
{
"columnName": "UPNSuffix",
"identifier": "UPNSuffix"
}
]
},
{
"entityType": "Host",
"fieldMappings": [
{
"columnName": "SrcHostname",
"identifier": "HostName"
}
]
}
],
"eventGroupingSettings": {
"aggregationKind": "AlertPerResult"
},
"OriginalUri": "https://github.com/Azure/Azure-Sentinel/blob/master/Solutions/Web Session Essentials/Analytic Rules/MultipleClientErrorsWithinShortTime.yaml",
"query": "// HTTP response status codes indicate whether a specific HTTP request has been successfully completed.\n// Please refer this for more details: https://developer.mozilla.org/en-US/docs/Web/HTTP/Status\nlet threshold = 100; // You can set threshold value that suits your environment\n_Im_WebSession(starttime=ago(1h))\n| where toint(EventResultDetails) between (400 .. 499)\n| summarize\n TotalErrorCount = count(),\n EventStartTime = min(TimeGenerated),\n EventEndTime = max(TimeGenerated),\n URLs=make_set(Url, 100),\n EventResultDetailsSet=make_set(EventResultDetails,10)\n by SrcIpAddr, bin(TimeGenerated, 5m), SrcUsername, SrcHostname\n| where TotalErrorCount > threshold\n| extend Name = iif(SrcUsername contains \"@\", tostring(split(SrcUsername,'@',0)[0]),SrcUsername), UPNSuffix = iif(SrcUsername contains \"@\",tostring(split(SrcUsername,'@',1)[0]),\"\"), Threshold=threshold\n",
"queryFrequency": "PT1H",
"queryPeriod": "PT1H",
"severity": "Medium",
"status": "Available",
"subTechniques": [],
"suppressionDuration": "PT1H",
"suppressionEnabled": false,
"tactics": [
"CommandAndControl",
"InitialAccess"
],
"tags": [
{
"Schema": "WebSession",
"SchemaVersion": "0.2.6"
}
],
"techniques": [
"T1071",
"T1133",
"T1190"
],
"templateVersion": "1.0.0",
"triggerOperator": "GreaterThan",
"triggerThreshold": 0
},
"type": "Microsoft.OperationalInsights/workspaces/providers/alertRules"
}
]
}