Detectionmediumtest

Cisco Duo Successful MFA Authentication Via Bypass Code

Detects when a successful MFA authentication occurs due to the use of a bypass code. A bypass code is a temporary passcode created by an administrator for a specific user to access a Duo-protected application. These are generally used as "backup codes," so that enrolled users who are having problems with their mobile devices (e.g., mobile service is disrupted, the device is lost or stolen, etc.) or who temporarily can't use their enrolled devices (on a plane without mobile data services) can still access their Duo-protected systems.

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Launch
Nikita KhalimonenkovCreated Wed Apr 176f7e1c10-2dc9-4312-adb6-9574ff09a5c8identity
Log Source
Ciscoduo
ProductCisco← raw: cisco
Serviceduo← raw: duo
Detection Logic
Detection Logic1 selector
detection:
    selection:
        event_type: authentication
        reason: bypass_user
    condition: selection
False Positives

Legitimate user that was assigned on purpose to a bypass group

Rule Metadata
Rule ID
6f7e1c10-2dc9-4312-adb6-9574ff09a5c8
Status
test
Level
medium
Type
Detection
Created
Wed Apr 17
Path
rules/identity/cisco_duo/cisco_duo_mfa_bypass_via_bypass_code.yml
Raw Tags
attack.credential-accessattack.defense-evasionattack.initial-access
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