Query: rule covering Detects an executable, which is not an internet browser or known application, initiating network connections to legit po
Matching passage: Sigma rule: Detects an executable, which is not an internet browser or known application, initiating network connections to legit po. Logsource: windows / network_connection. Rule: title: New Connection Initiated To Potential Dead Drop Resolver Domain id: 297ae038-edc2-4b2e-bb3e-7c5fc94dd5c7 related: - id: d7b09985-95a3-44be-8450-b6eadf49833e type: obsolete - id: 8b48ad89-10d8-4382-a546-50588c410f0d type: similar - id: d635249d-86b5-4dad-a8c7-d7272b788586 type: similar - id: 52182dfb-afb7-41db-b4bc-5336cb29b464 type: similar - id: ae02ed70-11aa-4a22-b397-c0d0e8f6ea99 type: similar - id: e0f8ab85-0ac9-423b-a73a-81b3c7b1aa97 type: similar - id: 7b434893-c57d-4f41-908d-6a17bf1ae98f type: similar - id: 8518ed3d-f7c9-4601-a26c-f361a4256a0c type: similar - id: 42a5f1e7-9603-4f6d-97ae-3f37d130d794 type: similar - id: 56454143-524f-49fb-b1c6-3fb8b1ad41fb type: similar - id: b6e04788-29e1-4557-bb14-77f761848ab8 type: similar - id: a0d7e4d2-bede-4141-8896-bc6e237e977c type: similar status: test description: 'Detects an executable, which is not an internet browser or known application, initiating network connections to legit popular websites, which were seen to be used as dead drop resolvers in previous attacks. In this context attackers leverage known websites such as "facebook", "youtube", etc. In order to pass through undetected. ' references: - https://web.archive.org/web/20220830134315/https://content.fireeye.com/apt-41/rpt-apt41/ - https://securelist.com/the-tetrade-brazilian-banking-malware/97779/ - https://blog.bushidotoken.net/2021/04/dead-drop-resolvers-espionage-inspired.html - https://github.com/kleiton0x00/RedditC2 - https://twitter.com/kleiton0x7e/status/1600567316810551296 - https://www.linkedin.com/posts/kleiton-kurti_github-kleiton0x00redditc2-abusing-reddit-activity-7009939662462984192-5DbI/?originalSubdomain=al author: Sorina Ionescu, X__Junior (Nextron Systems) date: 2022-08-17 modified: 2026-03-29 tags: - attack.command-and-control - attack.t1102 - attack.t1102.001 logsource: category: network_connection product: windows detection: selection: Initiated: 'true' DestinationHostname|endswith: - .t.me - 0x0.st - 4shared.com - abuse.ch - anonfiles.com - bashupload.com - cdn.discordapp.com - chunk.io - cloudflare.com - ddns.net - discord.com - docs.google.com - drive.google.com - dropbox.com - dropmefiles.com - facebook.com - feeds.rapidfeeds.com - fotolog.com - ghostbin.co/ - githubusercontent.com - gofile.io - hastebin.com - imgur.com - livejournal.com - mediafire.com - mega.co.nz - mega.nz - onedrive.com - pages.dev - paste.ee - pastebin.com - pastebin.pl - pastetext.net - pixeldrain.com - privatlab.com - privatlab.net - reddi
Near-miss passage: Sigma rule: Indicates anomalous behavior based on suspicious sign-in activity across multiple tenants from different countries in th. Logsource: azure / riskdetection. Rule: title: Suspicious Browser Activity id: 944f6adb-7a99-4c69-80c1-b712579e93e6 status: test description: Indicates anomalous behavior based on suspicious sign-in activity across multiple tenants from different countries in the same browser references: - https://learn.microsoft.com/en-us/entra/id-protection/concept-identity-protection-risks#suspicious-browser - https://learn.microsoft.com/en-us/entra/architecture/security-operations-user-accounts#unusual-sign-ins author: Mark Morowczynski '@markmorow', Gloria Lee, '@gleeiamglo' date: 2023-09-03 tags: - attack.stealth - attack.t1078 - attack.persistence - attack.privilege-escalation - attack.initial-access logsource: product: azure service: riskdetection detection: selection: riskEventType: suspiciousBrowser condition: selection falsepositives: - We recommend investigating the sessions flagged by this detection in the context of other sign-ins from the user. level: high