Sigma rule: Publicly Accessible RDP Service

A detection rule from the SigmaHQ repository, shown as its author published it. Dataset version ref-65241aba41c3, updated 2024-03-13T00:00:00.000Z.

Rule

Title
Publicly Accessible RDP Service
Status
test
Level
high
Author
Josh Brower @DefensiveDepth
Date
2020-08-22
Modified
2024-03-13
File
rules/network/zeek/zeek_rdp_public_listener.yml
Commit
ccbb0369507f796db0b0ae6854c8a2be471b9d84

Detects connections from routable IPs to an RDP listener. Which is indicative of a publicly-accessible RDP service.

Log source

product
zeek
service
rdp

Detection

selection:
    id.orig_h|cidr:
        - '::1/128'  # IPv6 loopback
        - '10.0.0.0/8'
        - '127.0.0.0/8'
        - '172.16.0.0/12'
        - '192.168.0.0/16'
        - '169.254.0.0/16'
        - '2620:83:8000::/48'
        - 'fc00::/7'  # IPv6 private addresses
        - 'fe80::/10'  # IPv6 link-local addresses
# approved_rdp:
  # dst_ip:
    # - x.x.x.x
condition: not selection # and not approved_rdp

False positives (as the rule lists them)

  • Although it is recommended to NOT have RDP exposed to the internet, verify that this is a) allowed b) the server has not already been compromised via some brute force or remote exploit since it has been exposed to the internet. Work to secure the server if you are unable to remove it from being exposed to the internet.

Tags

  • attack.lateral-movement
  • attack.t1021.001

MITRE ATT&CK ids this rule names

Read on 2026-11-03T00:58:21.399Z under licence sigma-drl-1.1@d5f4c36a from https://github.com/SigmaHQ/sigma/blob/ccbb0369507f796db0b0ae6854c8a2be471b9d84/rules/network/zeek/zeek_rdp_public_listener.yml

Sources and licences

  • SigmaHQ

    "Publicly Accessible RDP Service" by Josh Brower @DefensiveDepth (SigmaHQ). Rule: https://github.com/SigmaHQ/sigma/blob/ccbb0369507f796db0b0ae6854c8a2be471b9d84/rules/network/zeek/zeek_rdp_public_listener.yml.
    Licensed under the Detection Rule License (DRL) 1.1: https://github.com/SigmaHQ/Detection-Rule-License

    Detection Rule License (DRL) 1.1

Cite this page

Dragons Eye Ransomware Tracker, "Sigma rule: Publicly Accessible RDP Service",
entity page, dataset version ref-65241aba41c3, updated 2024-03-13T00:00:00.000Z,
https://ransomware-tracker.com/detections/sigma/1fc0809e-06bf-4de3-ad52-25e5263b7623 (accessed 2026-11-03).
Underlying source: SigmaHQ rule 1fc0809e-06bf-4de3-ad52-25e5263b7623, commit ccbb0369507f796db0b0ae6854c8a2be471b9d84.

Pages change. The dataset version identifies the data, but no archive of old versions is kept, so this citation cannot be replayed later.