diff --git a/ql/lib/codeql/actions/security/CachePoisoningQuery.qll b/ql/lib/codeql/actions/security/CachePoisoningQuery.qll
index df2e1db3bdd..b60eb7da761 100644
--- a/ql/lib/codeql/actions/security/CachePoisoningQuery.qll
+++ b/ql/lib/codeql/actions/security/CachePoisoningQuery.qll
@@ -1,4 +1,5 @@
 import actions
+import codeql.actions.dataflow.ExternalFlow
 
 string defaultBranchTriggerEvent() {
   result =