Query: Sigma YAML for zeek / dce_rpc
Matching passage: Sigma rule: Detects usage of the windows RPC library Encrypting File System Remote Protocol (MS-EFSRPC). Variations of this RPC are. Logsource: zeek / dce_rpc. Rule: title: Potential PetitPotam Attack Via EFS RPC Calls id: 4096842a-8f9f-4d36-92b4-d0b2a62f9b2a status: test description: "Detects usage of the windows RPC library Encrypting File System Remote Protocol (MS-EFSRPC). Variations of this\ \ RPC are used within the attack refereed to as PetitPotam.\nThe usage of this RPC function should be rare if ever used\ \ at all.\nThus usage of this function is uncommon enough that any usage of this RPC function should warrant further investigation\ \ to determine if it is legitimate.\n View surrounding logs (within a few minutes before and after) from the Source IP to.\ \ Logs from from the Source IP would include dce_rpc, smb_mapping, smb_files, rdp, ntlm, kerberos, etc..'\n" references: - https://github.com/topotam/PetitPotam/blob/d83ac8f2dd34654628c17490f99106eb128e7d1e/PetitPotam/PetitPotam.cpp - https://msrc.microsoft.com/update-guide/vulnerability/ADV210003 - https://vx-underground.org/archive/Symantec/windows-vista-network-attack-07-en.pdf - https://threatpost.com/microsoft-petitpotam-poc/168163/ author: '@neu5ron, @Antonlovesdnb, Mike Remen' date: 2021-08-17 modified: 2022-11-28 tags: - attack.collection - attack.credential-access - attack.t1557.001 - attack.t1187 logsource: product: zeek service: dce_rpc detection: selection: operation|startswith: efs condition: selection falsepositives: - Uncommon but legitimate windows administrator or software tasks that make use of the Encrypting File System RPC Calls. Verify if this is common activity (see description). level: medium
Near-miss passage: Sigma rule: Detects when a user enables DNS-over-HTTPS. This can be used to hide internet activity or be used to hide the process of. Logsource: windows / registry_set. Rule: title: DNS-over-HTTPS Enabled by Registry id: 04b45a8a-d11d-49e4-9acc-4a1b524407a5 status: test description: 'Detects when a user enables DNS-over-HTTPS. This can be used to hide internet activity or be used to hide the process of exfiltrating data. With this enabled organization will lose visibility into data such as query type, response and originating IP that are used to determine bad actors. ' references: - https://www.tenforums.com/tutorials/151318-how-enable-disable-dns-over-https-doh-microsoft-edge.html - https://github.com/elastic/detection-rules/issues/1371 - https://chromeenterprise.google/policies/?policy=DnsOverHttpsMode - https://admx.help/HKLM/Software/Policies/Mozilla/Firefox/DNSOverHTTPS author: Austin Songer date: 2021-07-22 modified: 2023-08-17 tags: - attack.persistence - attack.stealth - attack.defense-impairment - attack.t1140 - attack.t1112 logsource: product: windows category: registry_set detection: selection_edge: TargetObject|endswith: \SOFTWARE\Policies\Microsoft\Edge\BuiltInDnsClientEnabled Details: DWORD (0x00000001) selection_chrome: TargetObject|endswith: \SOFTWARE\Google\Chrome\DnsOverHttpsMode Details: secure selection_firefox: TargetObject|endswith: \SOFTWARE\Policies\Mozilla\Firefox\DNSOverHTTPS\Enabled Details: DWORD (0x00000001) condition: 1 of selection_* falsepositives: - Unlikely level: medium