MFA Fatigue (OKTA)

Status: available
Severity: medium
Time window: 1h
Group by: TimeGenerated, actor_alternateId_s, actor_displayName_s, authenticationContext_externalSessionId_s, outcome_result_s
Source: github.com/Azure/Azure-Sentinel

MFA fatigue attack is a cybersecurity threat where attackers exploit user exhaustion from multi-factor authentication prompts to trick them into providing their MFA details thus compromising their own security. The query identifies MFA fatigue attempts in the Okta data. Ref: https://www.okta.com/blog/identity-security/mfa-fatigue-growing-security-concern/.

MITRE ATT&CK coverage

Tactic	Techniques
Credential Access	`T1621` Multi-Factor Authentication Request Generation

Event coverage

Provider	Event
Okta-system	system.push.send_factor_verify_push
Okta-user	user.authentication.auth_via_mfa
Okta-user	user.mfa.okta_verify.deny_push

Rules detecting the same action

Other rules on this platform that filter on the same API call or operation.

First Occurrence of Okta User Session Started via Proxy (Elastic)
Okta AiTM Phishing Attempt Blocked by FastPass (Panther)
Okta Fast Pass phishing Detection (Kusto)
Okta FastPass Phishing Detection (Sigma)
Okta FastPass Phishing Detection (Elastic)
Okta MFA Bruteforce Attack (YARA-L)
Okta MFA Exhaustion Hunt (Splunk)
Okta Mismatch Between Source And Response For Verify Push Request (YARA-L)

Rule body kusto

id: c2697b81-7fe9-4f57-ba1d-de46c6f91f9c
name: MFA Fatigue (OKTA)
description: |
    'MFA fatigue attack is a cybersecurity threat where attackers exploit user exhaustion from multi-factor authentication prompts to trick them into providing their MFA details thus compromising their own security. The query identifies MFA fatigue attempts in the Okta data. 
     Ref: https://www.okta.com/blog/identity-security/mfa-fatigue-growing-security-concern/.'
severity: Medium
status: Available
requiredDataConnectors:
  - connectorId: OktaSSO
    dataTypes:
      - Okta_CL
  - connectorId: OktaSSOv2
    dataTypes:
      - OktaSSO
queryFrequency: 1h
queryPeriod: 1h
triggerOperator: gt
triggerThreshold: 0
tactics:
  - CredentialAccess
relevantTechniques:
  - T1621
query: |
  let PushThreshold = 10;
  OktaSSO
  | where ((eventType_s =="user.authentication.auth_via_mfa" and column_ifexists('debugContext_debugData_factor_s', '') == "OKTA_VERIFY_PUSH") or eventType_s == "system.push.send_factor_verify_push" or eventType_s == "user.mfa.okta_verify.deny_push") 
  | summarize IPAddress = make_set(client_ipAddress_s,100), City = make_set(client_geographicalContext_city_s,100),
            successes = countif(eventType_s == "user.authentication.auth_via_mfa"),
            denies = countif(eventType_s == "user.mfa.okta_verify.deny_push"),
            pushes = countif(eventType_s == "system.push.send_factor_verify_push") by TimeGenerated, authenticationContext_externalSessionId_s, actor_alternateId_s,actor_displayName_s, outcome_result_s 
  | summarize lasttime = max(TimeGenerated), firsttime = min(TimeGenerated),
            successes = sum(successes), failures = sum(denies), pushes = sum(pushes) by  authenticationContext_externalSessionId_s, actor_alternateId_s,actor_displayName_s, outcome_result_s 
  | extend seconds = lasttime - firsttime
  | where pushes >  (PushThreshold)
  | extend totalattempts = successes + failures
  | extend finding = case(
              failures == pushes and pushes > 1, "Authentication attempts not successful because multiple pushes denied",
              totalattempts == 0, "Multiple pushes sent and ignored",
              successes > 0 and pushes > 3, "Multiple pushes sent, eventual successful authentication!",
              "Normal authentication pattern")
entityMappings:
  - entityType: Account
    fieldMappings:
      - identifier: Name
        columnName: actor_alternateId_s
      - identifier: DisplayName
        columnName: actor_displayName_s
version: 1.1.2
kind: Scheduled

Stages and Predicates

Parameters

let PushThreshold = 10;

Stage 1: `source`

OktaSSO

Stage 2: `where`

| where ((eventType_s =="user.authentication.auth_via_mfa" and column_ifexists('debugContext_debugData_factor_s', '') == "OKTA_VERIFY_PUSH") or eventType_s == "system.push.send_factor_verify_push" or eventType_s == "user.mfa.okta_verify.deny_push")

Stage 3: `summarize`

| summarize IPAddress = make_set(client_ipAddress_s,100), City = make_set(client_geographicalContext_city_s,100),
          successes = countif(eventType_s == "user.authentication.auth_via_mfa"),
          denies = countif(eventType_s == "user.mfa.okta_verify.deny_push"),
          pushes = countif(eventType_s == "system.push.send_factor_verify_push") by TimeGenerated, authenticationContext_externalSessionId_s, actor_alternateId_s,actor_displayName_s, outcome_result_s

Stage 4: `summarize`

| summarize lasttime = max(TimeGenerated), firsttime = min(TimeGenerated),
          successes = sum(successes), failures = sum(denies), pushes = sum(pushes) by  authenticationContext_externalSessionId_s, actor_alternateId_s,actor_displayName_s, outcome_result_s

Threshold: gt 10

Stage 5: `extend`

| extend seconds = lasttime - firsttime

Stage 6: `where`

| where pushes >  (PushThreshold)

Stage 7: `extend`

| extend totalattempts = successes + failures

Stage 8: `extend`

| extend finding = case(
            failures == pushes and pushes > 1, "Authentication attempts not successful because multiple pushes denied",
            totalattempts == 0, "Multiple pushes sent and ignored",
            successes > 0 and pushes > 3, "Multiple pushes sent, eventual successful authentication!",
            "Normal authentication pattern")

finding =

iffailures == "pushes" and pushes > 1"Authentication attempts not successful because multiple pushes denied"

eliftotalattempts == 0"Multiple pushes sent and ignored"

elifsuccesses > 0 and pushes > 3"Multiple pushes sent, eventual successful authentication!"

else"Normal authentication pattern"

Indicators

Each row is a field, operator, and value that the rule matches. The corpus column counts how many other rules in the catalog look for the same combination: high numbers point to widely-used, community-vetted indicators. Blank or 1 shows that the indicator is specific to this rule.

Field	Kind	Values
`debugContext_debugData_factor_s`	eq	`OKTA_VERIFY_PUSH` transforms: `column_ifexists`, `cased`
`eventType_s`	eq	`system.push.send_factor_verify_push` transforms: `cased` `user.authentication.auth_via_mfa` transforms: `cased` `user.mfa.okta_verify.deny_push` transforms: `cased`
`pushes`	gt	`10` transforms: `cased`

Output fields

Fields the rule emits when it matches. Chronicle authors list these in the outcome block; they appear on the detection and $risk_score drives alerting. Sentinel / Defender XDR rules build them up through project / summarize / extend stages. Sentinel maps these into alert fields via entityMappings and customDetails; Defender XDR custom detections surface them as alert fields directly.

Field	Source
`actor_alternateId_s`	`summarize`
`actor_displayName_s`	`summarize`
`authenticationContext_externalSessionId_s`	`summarize`
`failures`	`summarize`
`firsttime`	`summarize`
`lasttime`	`summarize`
`outcome_result_s`	`summarize`
`pushes`	`summarize`
`successes`	`summarize`
`seconds`	`extend`
`totalattempts`	`extend`
`finding`	`extend`

`j` / `k`	Scroll down / up
`d` / `u`	Half-page down / up
`gg` / `G`	Top / bottom
`h` / `l`	History back / forward
`f`	Follow link (`Shift` = new tab)
`/`	Focus search
`?`	Toggle this help
`↑` / `↓`	Navigate search results
`Enter`	Open highlighted result
`Esc`	Close results / dialog

`type:`	`events` / `rules` / `providers`
`vendor:`	`sigma` / `elastic` / `splunk` / `kusto` / `chronicle` (vendor name alone also works: `sigma:`, `kql:`, `secops:`…)
`tactic:`	TA-id, slug, or name: `credential_access`, `TA0006`
`technique:`	technique or sub-technique ID: `T1003`, `T1003.001` (alias `tech:`)
`severity:`	`critical` / `high` / `medium` / `low` / `informational` (alias `sev:`)
`risk_score`	Numeric comparison on the Elastic risk score (0 to 100): `risk_score>50`, `risk_score<=20`, `risk_score=99` (alias `risk`; Elastic rules only)
`stages:`	Rules with exactly N pipeline stages
`correlation:`	`single_event` / `sequence` / `alternatives` / `alternatives_cross_log` / `all_required` / `correlated`
`with:`	Co-occurrence event-id; stacks (`with:4624 with:4769`) to require all, while a comma list in one occurrence (`with:4624,4769`) is an either-or group. Implies multi-event
`like:`	Structural neighbors of a rule slug (equivalents + subsumption stricter / broader): `like:comsvcs_lsass_memory_dump-splunk-sysmon`
`groupby:`	Entity-grouping substring match against `group_by_keys`: `groupby:user`, `groupby:host`
`uses:`	Rules whose predicate tree touches the field (any kind, any value): `uses:CommandLine`
`excludes:`	Rules with top-level `not()` clauses on the field (FP whitelists): `excludes:ParentImage`
`field:` / `value:`	Predicate search; narrows rule cards to those with a matching leaf and drives the indicator tier. Unquoted = substring, wildcards allowed (`value:mimikatz`)
`indicator:`	Shorthand for `field:F value:V`: `indicator:Image=*\powershell.exe`
`kind:`	Filter by predicate kind. Narrows rule cards to those carrying a matching predicate leaf (`vendor:elastic kind:cidr_match`) and drives the indicator tier: `contains` / `starts_with` / `ends_with` / `regex` / `cidr` / `eq` / `in` … (operator aliases `op:`/`match:`)
`has:` / `no:`	`sample`, `field`, `notes`, `refs`, `trace`, `thirdparty`, `rule`, `pattern`, `timewindow`, `threshold`, `newterms`, `sigma`/`elastic`/`splunk`/`kusto`/`chronicle`
`-op:val`	Exclude matches; works on most operators but not `type:`/`like:`/`has:`/`no:` (use `no:<flag>` to exclude a rule flag): `tactic:execution -vendor:splunk`. Standalone `-kind:`/`-field:`/`-value:` drop every rule carrying a matching predicate leaf (`type:rules -kind:is_null`)
`field:"…"` / `value:"…"`	Quoted value = anchored exact match (also allows spaces): `value:"net user"`
`a,b`	Comma = OR inside one operator (`vendor:sigma,elastic`, `severity:high,critical`); repeating a facet merges the same way. `field:`/`value:` never split (literal commas)
`vendors:` / `stage:`	Singular and plural spellings fold to the canonical operator and value: `tactics:` = `tactic:`, `type:event` = `type:events`, `correlation:sequences` = `correlation:sequence`, `has:thresholds` = `has:threshold`
`"quoted phrase"`	Exact-match a multi-word phrase (free text)

MFA Fatigue (OKTA)

MITRE ATT&CK coverage

Event coverage

Rules detecting the same action

Rule body kusto

Stages and Predicates

Parameters

Stage 1: `source`

Stage 2: `where`

Stage 3: `summarize`

Stage 4: `summarize`

Stage 5: `extend`

Stage 6: `where`

Stage 7: `extend`

Stage 8: `extend`

Indicators

Output fields

Keyboard shortcuts

Search operators

MFA Fatigue (OKTA)

MITRE ATT&CK coverage

Event coverage

Rules detecting the same action

Rule body kusto

Stages and Predicates

Parameters

Stage 1: source

Stage 2: where

Stage 3: summarize

Stage 4: summarize

Stage 5: extend

Stage 6: where

Stage 7: extend

Stage 8: extend

Indicators

Output fields

Stage 1: `source`

Stage 2: `where`

Stage 3: `summarize`

Stage 4: `summarize`

Stage 5: `extend`

Stage 6: `where`

Stage 7: `extend`

Stage 8: `extend`