diff --git a/clusters/threat-actor.json b/clusters/threat-actor.json
index 4fdb789b..943706b5 100644
--- a/clusters/threat-actor.json
+++ b/clusters/threat-actor.json
@@ -17,7 +17,7 @@
         "country": "CN",
         "refs": [
           "https://en.wikipedia.org/wiki/PLA_Unit_61398",
-          "http://intelreport.mandiant.com/Mandiant_APT1_Report.pdf"
+          "https://www.fireeye.com/content/dam/fireeye-www/services/pdfs/mandiant-apt1-report.pdf"
         ]
       },
       "description": "PLA Unit 61398 (Chinese: 61398部队, Pinyin: 61398 bùduì) is the Military Unit Cover Designator (MUCD)[1] of a People's Liberation Army advanced persistent threat unit that has been alleged to be a source of Chinese computer hacking attacks",