Update open_redirect_youtube.yml (#1086)

detection-rules/open_redirect_youtube.yml

@@ -11,7 +11,29 @@ source: |
           .href_url.domain.root_domain == "youtube.com"
           and strings.icontains(.href_url.url, "attribution_link?")
   )
-  and sender.email.domain.root_domain != "youtube.com"
+  and (
+    any(distinct(headers.hops, .authentication_results.dmarc is not null),
+        .authentication_results.dmarc_details.from.domain != "youtube.com"
+    )
+  )
+  
+  // negate highly trusted sender domains unless they fail DMARC authentication
+  and (
+    (
+      sender.email.domain.root_domain in $high_trust_sender_root_domains
+      and (
+        any(distinct(headers.hops, .authentication_results.dmarc is not null),
+            strings.ilike(.authentication_results.dmarc, "*fail")
+        )
+      )
+    )
+    or sender.email.domain.root_domain not in $high_trust_sender_root_domains
+  )
+  and (
+    not profile.by_sender().solicited
+    or profile.by_sender().any_messages_malicious_or_spam
+  )
+
 attack_types:
   - "Credential Phishing"
   - "Malware/Ransomware"