Query: rule covering Detects remote RPC calls to possibly abuse remote encryption service via MS-EFSR
Matching passage: Sigma rule: Detects remote RPC calls to possibly abuse remote encryption service via MS-EFSR. Logsource: rpc_firewall / application. Rule: title: Remote Encrypting File System Abuse id: 5f92fff9-82e2-48eb-8fc1-8b133556a551 status: test description: Detects remote RPC calls to possibly abuse remote encryption service via MS-EFSR references: - https://msrc.microsoft.com/update-guide/vulnerability/CVE-2021-36942 - https://github.com/jsecurity101/MSRPC-to-ATTACK/blob/ddd4608fe8684fcf2fcf9b48c5f0b3c28097f8a3/documents/MS-EFSR.md - https://github.com/zeronetworks/rpcfirewall - https://zeronetworks.com/blog/stopping-lateral-movement-via-the-rpc-firewall/ author: Sagie Dulce, Dekel Paz date: 2022-01-01 tags: - attack.lateral-movement logsource: product: rpc_firewall category: application definition: 'Requirements: install and apply the RPC Firewall to all processes with "audit:true action:block uuid:df1941c5-fe89-4e79-bf10-463657acf44d or c681d488-d850-11d0-8c52-00c04fd90f7e' detection: selection: EventLog: RPCFW EventID: 3 InterfaceUuid: - df1941c5-fe89-4e79-bf10-463657acf44d - c681d488-d850-11d0-8c52-00c04fd90f7e condition: selection falsepositives: - Legitimate usage of remote file encryption level: high
Near-miss passage: Sigma rule: Detects base64 encoded .NET reflective loading of Assembly. Logsource: windows / process_creation. Rule: title: PowerShell Base64 Encoded Reflective Assembly Load id: 62b7ccc9-23b4-471e-aa15-6da3663c4d59 related: - id: 9c0295ce-d60d-40bd-bd74-84673b7592b1 type: similar status: test description: Detects base64 encoded .NET reflective loading of Assembly references: - https://github.com/Neo23x0/Raccine/blob/20a569fa21625086433dcce8bb2765d0ea08dcb6/yara/mal_revil.yar - https://thedfirreport.com/2022/05/09/seo-poisoning-a-gootloader-story/ author: Christian Burkard (Nextron Systems), pH-T (Nextron Systems) date: 2022-03-01 modified: 2023-01-30 tags: - attack.execution - attack.stealth - attack.t1059.001 - attack.t1027 - attack.t1620 logsource: category: process_creation product: windows detection: selection: CommandLine|contains: - WwBSAGUAZgBsAGUAYwB0AGkAbwBuAC4AQQBzAHMAZQBtAGIAbAB5AF0AOgA6AEwAbwBhAGQAKA - sAUgBlAGYAbABlAGMAdABpAG8AbgAuAEEAcwBzAGUAbQBiAGwAeQBdADoAOgBMAG8AYQBkACgA - bAFIAZQBmAGwAZQBjAHQAaQBvAG4ALgBBAHMAcwBlAG0AYgBsAHkAXQA6ADoATABvAGEAZAAoA - AFsAcgBlAGYAbABlAGMAdABpAG8AbgAuAGEAcwBzAGUAbQBiAGwAeQBdADoAOgAoACIATABvAGEAZAAiAC - BbAHIAZQBmAGwAZQBjAHQAaQBvAG4ALgBhAHMAcwBlAG0AYgBsAHkAXQA6ADoAKAAiAEwAbwBhAGQAIgAp - AWwByAGUAZgBsAGUAYwB0AGkAbwBuAC4AYQBzAHMAZQBtAGIAbAB5AF0AOgA6ACgAIgBMAG8AYQBkACIAK - WwBSAGUAZgBsAGUAYwB0AGkAbwBuAC4AQQBzAHMAZQBtAGIAbAB5AF0AOgA6ACgAIgBMAG8AYQBkACIAKQ - sAUgBlAGYAbABlAGMAdABpAG8AbgAuAEEAcwBzAGUAbQBiAGwAeQBdADoAOgAoACIATABvAGEAZAAiACkA - bAFIAZQBmAGwAZQBjAHQAaQBvAG4ALgBBAHMAcwBlAG0AYgBsAHkAXQA6ADoAKAAiAEwAbwBhAGQAIgApA - WwByAGUAZgBsAGUAYwB0AGkAbwBuAC4AYQBzAHMAZQBtAGIAbAB5AF0AOgA6AEwAbwBhAGQAKA - sAcgBlAGYAbABlAGMAdABpAG8AbgAuAGEAcwBzAGUAbQBiAGwAeQBdADoAOgBMAG8AYQBkACgA - bAHIAZQBmAGwAZQBjAHQAaQBvAG4ALgBhAHMAcwBlAG0AYgBsAHkAXQA6ADoATABvAGEAZAAoA condition: selection falsepositives: - Unlikely level: high