SigmaHQ/rules-unsupported/net_dns_high_subdomain_rate.yml
Thomas Patzke 924e1feb54 UUIDs + moved unsupported logic
* Added UUIDs to all contributed rules
* Moved unsupported logic directory out of rules/ because this breaks CI
  testing.
2019-12-19 23:56:36 +01:00

43 lines
1.5 KiB
YAML

title: High DNS subdomain requests rate per domain
id: 8198e9a8-e38f-4ba5-8f16-882b1c0f880e
description: High rate of unique Fully Qualified Domain Names (FQDN) requests per root domain (eTLD+1) in short period of time
author: Daniil Yugoslavskiy, oscd.community
date: 2019/10/21
modified: 2019/11/04
tags:
- attack.exfiltration
- attack.t1048
logsource:
category: dns
detection:
dns_question_name:
query: "*"
default_list_of_well_known_domains:
query_etld_plus_one:
- "akadns.net"
- "akamaiedge.net"
- "amazonaws.com"
- "apple.com"
- "apple-dns.net"
- "cloudfront.net"
- "icloud.com"
- "in-addr.arpa"
- "google.com"
- "yahoo.com"
- "dropbox.com"
- "windowsupdate.com"
- "microsoftonline.com"
- "s-microsoft.com"
- "office365.com"
- "linkedin.com"
timeframe: 15m
condition: count(subdomain) per query_etld_plus_one per computer_name > 200 and not default_list_of_well_known_domains
# for each host in timeframe
# for each dns_question_etld_plus_one
# if number of dns_question_name > 200
# dns_question_etld_plus_one is not in default_list_of_well_known_domains
falsepositives:
- Legitimate domain name requested, which should be added to whitelist
level: high
status: experimental