Detection rules › Sigma

Many Failed Logins

Status
test
Severity
high
Time window
5m
Log source
product aws, service cloudtrail
Author
Zach Mathis (@yamatosecurity)
Source
github.com/Yamato-Security/suzaku-rules

Detects multiple failed console login attempts, which may indicate an attacker attempting password guessing or password spraying. This rule can be evaded if the attacker uses a different source IP address for each login attempt, so you may want to not group by source IP address to detect that evasion. Also, you may want to group on user agents as well to reduce false positives, however, that will also make it easier to evade detection.

MITRE ATT&CK coverage

TacticTechniques
Initial AccessNo specific technique

Event coverage

Rules detecting the same action

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

Rule body yaml


title: Many Failed Logins
id: 68f8de62-97cd-4a9a-afba-7804fddf43d4
status: test
description: |
    Detects multiple failed console login attempts, which may indicate an attacker attempting password guessing or password spraying.
    This rule can be evaded if the attacker uses a different source IP address for each login attempt, so you may want to not group by source IP address to detect that evasion.
    Also, you may want to group on user agents as well to reduce false positives, however, that will also make it easier to evade detection.
references:
author: Zach Mathis (@yamatosecurity)
date: 2025-08-02
modified: 2025-08-02
tags:
    - attack.initial_access
logsource:
    product: aws
    service: cloudtrail
correlation:
    type: event_count
    rules:
        - Failed Console Login
    group-by:
        - sourceIPAddress
    timespan: 5m
    condition:
        gte: 3
    generate: false
level: high
---
title: Failed Console Login
id: 978c15f1-3468-42b2-bf0f-bb29ae6168cc
status: test
description: Detects failed console login attempts, which may indicate an attacker attempting to gain access to
references:
author: Zach Mathis (@yamatosecurity)
date: 2025-08-02
modified: 2025-08-02
tags:
    - attack.initial_access
logsource:
    product: aws
    service: cloudtrail
detection:
    selection:
        eventSource: signin.amazonaws.com
        eventName: 'ConsoleLogin'
        responseElements.ConsoleLogin: 'Failure'
    condition: selection
level: low

Stages and Predicates

Stage 0: condition

selection

Stage 1: selection

selection:
    eventSource: signin.amazonaws.com
    eventName: 'ConsoleLogin'
    responseElements.ConsoleLogin: 'Failure'

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.

FieldKindValues
eventNameeq
  • ConsoleLogin
eventSourceeq
  • signin.amazonaws.com
responseElements.ConsoleLogineq
  • Failure