Skip to content

ASR - Add detection rule for confusable character domains #3500

New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Open
wants to merge 2 commits into
base: main
Choose a base branch
from
+19 −0
Open

ASR - Add detection rule for confusable character domains #3500

Changes from all commits
Commits
Show all changes
2 commits
Select commit Hold shift + click to select a range
09bc6b4
Add detection rule for confusable character domains
morriscode Nov 8, 2025
2e2c7ac
Auto add rule ID
Nov 8, 2025
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
19 changes: 19 additions & 0 deletions detection-rules/link_domain_containing_confusable_characters_asr.yml
View file
Open in desktop
Original file line number Diff line number Diff line change
@@ -0,0 +1,19 @@
name: "Link: Domain contains confusable characters"
description: "Detects links containing Unicode confusable characters that could be used to spoof legitimate domains by replacing standard characters with visually similar alternatives."
type: "rule"
severity: "medium"
source: |
type.inbound
and any(body.links, .href_url.url != strings.replace_confusables(.href_url.url))
tags:
- "Attack surface reduction"
attack_types:
- "Credential Phishing"
tactics_and_techniques:
- "Evasion"
- "Lookalike domain"
- "Punycode"
detection_methods:
- "Content analysis"
- "URL analysis"
id: "75672610-e11c-5650-8139-43f12870f294"