Query: detect Detects an a non-browser process interacting with the Telegram API which could indicate use of a covert C2 in logs
Matching passage: Sigma rule: Detects an a non-browser process interacting with the Telegram API which could indicate use of a covert C2. Logsource: windows / network_connection. Rule: title: Suspicious Non-Browser Network Communication With Telegram API id: c3dbbc9f-ef1d-470a-a90a-d343448d5875 status: test description: Detects an a non-browser process interacting with the Telegram API which could indicate use of a covert C2 references: - https://www.ncsc.gov.uk/static-assets/documents/malware-analysis-reports/small-sieve/NCSC-MAR-Small-Sieve.pdf author: Nasreddine Bencherchali (Nextron Systems) date: 2023-05-19 tags: - attack.command-and-control - attack.exfiltration - attack.t1102 - attack.t1567 - attack.t1105 logsource: product: windows category: network_connection detection: selection: DestinationHostname|contains: api.telegram.org filter_main_brave: Image|endswith: \brave.exe filter_main_chrome: Image: - C:\Program Files\Google\Chrome\Application\chrome.exe - C:\Program Files (x86)\Google\Chrome\Application\chrome.exe filter_main_firefox: Image: - C:\Program Files\Mozilla Firefox\firefox.exe - C:\Program Files (x86)\Mozilla Firefox\firefox.exe filter_main_ie: Image: - C:\Program Files (x86)\Internet Explorer\iexplore.exe - C:\Program Files\Internet Explorer\iexplore.exe filter_main_maxthon: Image|endswith: \maxthon.exe filter_main_edge_1: - Image|startswith: C:\Program Files (x86)\Microsoft\EdgeWebView\Application\ - Image|endswith: \WindowsApps\MicrosoftEdge.exe - Image: - C:\Program Files (x86)\Microsoft\Edge\Application\msedge.exe - C:\Program Files\Microsoft\Edge\Application\msedge.exe filter_main_edge_2: Image|startswith: - C:\Program Files (x86)\Microsoft\EdgeCore\ - C:\Program Files\Microsoft\EdgeCore\ Image|endswith: - \msedge.exe - \msedgewebview2.exe filter_main_opera: Image|endswith: \opera.exe filter_main_safari: Image|endswith: \safari.exe filter_main_seamonkey: Image|endswith: \seamonkey.exe filter_main_vivaldi: Image|endswith: \vivaldi.exe filter_main_whale: Image|endswith: \whale.exe condition: selection and not 1 of filter_main_* falsepositives: - Legitimate applications communicating with the Telegram API e.g. web browsers not in the exclusion list, app with an RSS etc. level: medium
Near-miss passage: Sigma rule: Detects when an attacker adds a new "DLLPathOverride" value to the "Natural Language" key in order to achieve persistenc. Logsource: windows / registry_set. Rule: title: Potential Persistence Via DLLPathOverride id: a1b1fd53-9c4a-444c-bae0-34a330fc7aa8 status: test description: Detects when an attacker adds a new "DLLPathOverride" value to the "Natural Language" key in order to achieve persistence which will get invoked by "SearchIndexer.exe" process references: - https://persistence-info.github.io/Data/naturallanguage6.html - https://www.hexacorn.com/blog/2018/12/30/beyond-good-ol-run-key-part-98/ author: Nasreddine Bencherchali (Nextron Systems) date: 2022-07-21 modified: 2023-08-17 tags: - attack.persistence logsource: category: registry_set product: windows detection: selection_root: TargetObject|contains: \SYSTEM\CurrentControlSet\Control\ContentIndex\Language\ selection_values: TargetObject|contains: - \StemmerDLLPathOverride - \WBDLLPathOverride - \StemmerClass - \WBreakerClass condition: all of selection_* falsepositives: - Unknown level: high