{"id":"50f852e6-af22-4c78-9ede-42ef36aa3453","title":"Potential Azure Browser SSO Abuse","description":"Detects abusing Azure Browser SSO by requesting OAuth 2.0 refresh tokens for an Azure-AD-authenticated Windows user (i.e. the machine is joined to Azure AD and a user logs in with their Azure AD account) wanting to perform SSO authentication in the browser.\nAn attacker can use this to authenticate to Azure AD in a browser as that user.\n","author":"Den Iuzvyk","status":"test","level":"low","date":"2020-07-15","modified":"2023-04-18","tags":["attack.persistence","attack.privilege-escalation","attack.execution","attack.stealth","attack.t1574.001"],"technique_ids":["T1574.001"],"logsource":{"category":"image_load","product":"windows"},"falsepositives":["False positives are expected since this rules is only looking for the DLL load event. This rule is better used in correlation with related activity"],"references":["https://posts.specterops.io/requesting-azure-ad-request-tokens-on-azure-ad-joined-machines-for-browser-sso-2b0409caad30"],"source_path":"rules/windows/image_load/image_load_dll_azure_microsoft_account_token_provider_dll_load.yml","source_sha256":"8a6c33b31b57d35958e06a11634e4be1f1695e85e2019d98116a5c21cd27e550","source_url":"https://github.com/anpa1200/sigma/blob/b249e9683190cffdcaf188ccbfb90bf4759844e1/rules/windows/image_load/image_load_dll_azure_microsoft_account_token_provider_dll_load.yml","license":"Detection Rule License 1.1","license_url":"https://github.com/SigmaHQ/Detection-Rule-License/blob/main/LICENSE.Detection.Rules.md","yaml":"title: Potential Azure Browser SSO Abuse\nid: 50f852e6-af22-4c78-9ede-42ef36aa3453\nstatus: test\ndescription: |\n    Detects abusing Azure Browser SSO by requesting OAuth 2.0 refresh tokens for an Azure-AD-authenticated Windows user (i.e. the machine is joined to Azure AD and a user logs in with their Azure AD account) wanting to perform SSO authentication in the browser.\n    An attacker can use this to authenticate to Azure AD in a browser as that user.\nreferences:\n    - https://posts.specterops.io/requesting-azure-ad-request-tokens-on-azure-ad-joined-machines-for-browser-sso-2b0409caad30\nauthor: Den Iuzvyk\ndate: 2020-07-15\nmodified: 2023-04-18\ntags:\n    - attack.persistence\n    - attack.privilege-escalation\n    - attack.execution\n    - attack.stealth\n    - attack.t1574.001\nlogsource:\n    category: image_load\n    product: windows\ndetection:\n    selection:\n        ImageLoaded: 'C:\\Windows\\System32\\MicrosoftAccountTokenProvider.dll'\n    filter_main_bgtaskhost:\n        Image|startswith:\n            - 'C:\\Windows\\System32\\'\n            - 'C:\\Windows\\SysWOW64\\'\n        Image|endswith: '\\BackgroundTaskHost.exe'\n        # CommandLine|contains: '-ServerNameBackgroundTaskHost.WebAccountProvider'\n    filter_optional_devenv:\n        Image|startswith:\n            - 'C:\\Program Files\\Microsoft Visual Studio\\'\n            - 'C:\\Program Files (x86)\\Microsoft Visual Studio\\'\n        Image|endswith: '\\IDE\\devenv.exe'\n    filter_optional_ie:\n        Image:\n            - 'C:\\Program Files (x86)\\Internet Explorer\\iexplore.exe'\n            - 'C:\\Program Files\\Internet Explorer\\iexplore.exe'\n    filter_optional_edge_1:\n        - Image|startswith: 'C:\\Program Files (x86)\\Microsoft\\EdgeWebView\\Application\\'\n        - Image|endswith: '\\WindowsApps\\MicrosoftEdge.exe'\n        - Image:\n              - 'C:\\Program Files (x86)\\Microsoft\\Edge\\Application\\msedge.exe'\n              - 'C:\\Program Files\\Microsoft\\Edge\\Application\\msedge.exe'\n    filter_optional_edge_2:\n        Image|startswith:\n            - 'C:\\Program Files (x86)\\Microsoft\\EdgeCore\\'\n            - 'C:\\Program Files\\Microsoft\\EdgeCore\\'\n        Image|endswith:\n            - '\\msedge.exe'\n            - '\\msedgewebview2.exe'\n    filter_optional_onedrive:\n        Image|endswith: '\\AppData\\Local\\Microsoft\\OneDrive\\OneDrive.exe'\n    filter_optional_null:\n        Image: null\n    condition: selection and not 1 of filter_main_* and not 1 of filter_optional_*\nfalsepositives:\n    - False positives are expected since this rules is only looking for the DLL load event. This rule is better used in correlation with related activity\nlevel: low\n","validation":"yaml_parsed_not_backend_compiled_or_live_validated","techniques":[{"key":"enterprise/T1574.001","id":"T1574.001","name":"DLL","page":"techniques/enterprise/T1574.001/"}],"data_path":"data/detection-rules/50f852e6-af22-4c78-9ede-42ef36aa3453.json","kind":"sigma"}