Query: Sigma rule for Detects suspicious manipulations of default accounts such as 'administrator' and 'guest'. For example 'enable' or 'disab
Matching passage: Sigma rule: Detects suspicious manipulations of default accounts such as 'administrator' and 'guest'. For example 'enable' or 'disab. Logsource: windows / process_creation. Rule: title: Suspicious Manipulation Of Default Accounts Via Net.EXE id: 5b768e71-86f2-4879-b448-81061cbae951 status: test description: Detects suspicious manipulations of default accounts such as 'administrator' and 'guest'. For example 'enable' or 'disable' accounts or change the password...etc references: - https://www.trellix.com/en-sg/about/newsroom/stories/threat-labs/lockergoga-ransomware-family-used-in-targeted-attacks.html - https://redacted.com/blog/bianlian-ransomware-gang-gives-it-a-go/ - https://www.microsoft.com/security/blog/2022/09/07/profiling-dev-0270-phosphorus-ransomware-operations/ author: Nasreddine Bencherchali (Nextron Systems) date: 2022-09-01 modified: 2023-02-21 tags: - attack.collection - attack.t1560.001 logsource: category: process_creation product: windows detection: selection_img: - Image|endswith: - \net.exe - \net1.exe - OriginalFileName: - net.exe - net1.exe selection_user_option: CommandLine|contains: ' user ' selection_username: CommandLine|contains: - ' Järjestelmänvalvoja ' - ' Rendszergazda ' - ' Администратор ' - ' Administrateur ' - ' Administrador ' - ' Administratör ' - ' Administrator ' - ' guest ' - ' DefaultAccount ' - ' "Järjestelmänvalvoja" ' - ' "Rendszergazda" ' - ' "Администратор" ' - ' "Administrateur" ' - ' "Administrador" ' - ' "Administratör" ' - ' "Administrator" ' - ' "guest" ' - ' "DefaultAccount" ' - ' ''Järjestelmänvalvoja'' ' - ' ''Rendszergazda'' ' - ' ''Администратор'' ' - ' ''Administrateur'' ' - ' ''Administrador'' ' - ' ''Administratör'' ' - ' ''Administrator'' ' - ' ''guest'' ' - ' ''DefaultAccount'' ' filter: CommandLine|contains|all: - guest - /active no condition: all of selection_* and not filter falsepositives: - Some false positives could occur with the admin or guest account. It depends on the scripts being used by the admins in your env. If you experience a lot of FP you could reduce the level to medium level: high
Near-miss passage: Sigma rule: Detects the use of TruffleHog for AWS credential validation by identifying GetCallerIdentity API calls where the userAge. Logsource: aws / cloudtrail. Rule: title: AWS STS GetCallerIdentity Enumeration Via TruffleHog id: 9b1b8e9b-0a5d-4af1-9d2f-4c4b6e7c2c9d status: experimental description: 'Detects the use of TruffleHog for AWS credential validation by identifying GetCallerIdentity API calls where the userAgent indicates TruffleHog. Threat actors leverage TruffleHog to enumerate and validate exposed AWS keys. Successful exploitation allows threat actors to confirm the validity of compromised AWS credentials, facilitating further unauthorized access and actions within the AWS environment. ' references: - https://www.rapid7.com/blog/post/tr-crimson-collective-a-new-threat-group-observed-operating-in-the-cloud/ - https://docs.aws.amazon.com/STS/latest/APIReference/API_GetCallerIdentity.html - https://github.com/trufflesecurity/trufflehog author: Adan Alvarez @adanalvarez date: 2025-10-12 tags: - attack.discovery - attack.t1087.004 logsource: product: aws service: cloudtrail detection: selection: eventSource: sts.amazonaws.com eventName: GetCallerIdentity userAgent|contains: TruffleHog condition: selection falsepositives: - Legitimate internal security scanning or key validation that intentionally uses TruffleHog. Authorize and filter known scanner roles, IP ranges, or assumed roles as needed. level: medium