Multi Factor Authentication Disabled For User Account

Status: test
Severity: medium
Log source: product azure, service auditlogs
Author: Harjot Singh (@cyb3rjy0t)
Source: github.com/SigmaHQ/sigma

Detects changes to the "StrongAuthenticationRequirement" value, where the state is set to "0" or "Disabled". Threat actors were seen disabling multi factor authentication for users in order to maintain or achieve access to the account. Also see in SIM Swap attacks.

MITRE ATT&CK coverage

Tactic	Techniques
Persistence	No specific technique
Credential Access	No specific technique

Event coverage

Provider	Event
Entra-AuditLogs	Update user

Rules detecting the same action

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

Authentication Method Changed for Privileged Account (Kusto)
Authentication Methods Changed for Privileged Account (Kusto)
Change to Authentication Method (Sigma)
Guest Users Invited To Tenant By Non Approved Inviters (Sigma)
New External User Granted Admin Role (Kusto)
NRT Authentication Methods Changed for VIP Users (Kusto)
Password Reset By User Account (Sigma)
Suspicious Login from deleted guest account (Kusto)

Rule body yaml

title: Multi Factor Authentication Disabled For User Account
id: b18454c8-0be3-41f7-86bc-9c614611b839
status: test
description: |
    Detects changes to the "StrongAuthenticationRequirement" value, where the state is set to "0" or "Disabled".
    Threat actors were seen disabling multi factor authentication for users in order to maintain or achieve access to the account. Also see in SIM Swap attacks.
references:
    - https://www.sans.org/blog/defending-against-scattered-spider-and-the-com-with-cybercrime-intelligence/
author: Harjot Singh (@cyb3rjy0t)
date: 2024-08-21
tags:
    - attack.credential-access
    - attack.persistence
logsource:
    product: azure
    service: auditlogs
    definition: 'Requirements: The TargetResources array needs to be mapped accurately in order for this rule to work'
detection:
    selection:
        LoggedByService: 'Core Directory'
        Category: 'UserManagement'
        OperationName: 'Update user'
        TargetResources.ModifiedProperties.DisplayName: 'StrongAuthenticationRequirement'
        TargetResources.ModifiedProperties.NewValue|contains: "State\":0"
    condition: selection
falsepositives:
    - Legitimate authorized activity.
level: medium

Stages and Predicates

Stage 0: `condition`

selection

Stage 1: `selection`

selection:
    LoggedByService: 'Core Directory'
    Category: 'UserManagement'
    OperationName: 'Update user'
    TargetResources.ModifiedProperties.DisplayName: 'StrongAuthenticationRequirement'
    TargetResources.ModifiedProperties.NewValue|contains: "State\":0"

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
`Category`	eq	`UserManagement`
`LoggedByService`	eq	`Core Directory`
`OperationName`	eq	`Update user`
`TargetResources.ModifiedProperties.DisplayName`	eq	`StrongAuthenticationRequirement`
`TargetResources.ModifiedProperties.NewValue`	match	`State":0`

`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
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`Enter`	Open highlighted result
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`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)

Multi Factor Authentication Disabled For User Account

MITRE ATT&CK coverage

Event coverage

Rules detecting the same action

Rule body yaml

Stages and Predicates

Stage 0: `condition`

Stage 1: `selection`

Indicators

Keyboard shortcuts

Search operators

Multi Factor Authentication Disabled For User Account

MITRE ATT&CK coverage

Event coverage

Rules detecting the same action

Rule body yaml

Stages and Predicates

Stage 0: condition

Stage 1: selection

Indicators

Stage 0: `condition`

Stage 1: `selection`