diff --git a/java/ql/lib/semmle/code/java/security/CleartextStorageAndroidFilesystemQuery.qll b/java/ql/lib/semmle/code/java/security/CleartextStorageAndroidFilesystemQuery.qll
index 649b684f06d..5b836e4c01f 100644
--- a/java/ql/lib/semmle/code/java/security/CleartextStorageAndroidFilesystemQuery.qll
+++ b/java/ql/lib/semmle/code/java/security/CleartextStorageAndroidFilesystemQuery.qll
@@ -5,7 +5,7 @@
 
 import java
 import semmle.code.java.dataflow.DataFlow
-import semmle.code.java.dataflow.ExternalFlow
+private import semmle.code.java.dataflow.ExternalFlow
 import semmle.code.java.security.CleartextStorageQuery
 import semmle.code.java.security.Files
 import semmle.code.xml.AndroidManifest
diff --git a/java/ql/lib/semmle/code/java/security/Files.qll b/java/ql/lib/semmle/code/java/security/Files.qll
index c017f0cedc1..8d802325792 100644
--- a/java/ql/lib/semmle/code/java/security/Files.qll
+++ b/java/ql/lib/semmle/code/java/security/Files.qll
@@ -1,7 +1,7 @@
 /** Provides classes and predicates to work with File objects. */
 
 import java
-import semmle.code.java.dataflow.ExternalFlow
+private import semmle.code.java.dataflow.ExternalFlow
 
 private class CreateFileSinkModels extends SinkModelCsv {
   override predicate row(string row) {
diff --git a/java/ql/lib/semmle/code/java/security/InformationLeak.qll b/java/ql/lib/semmle/code/java/security/InformationLeak.qll
index 3ea674521a0..f111f70719b 100644
--- a/java/ql/lib/semmle/code/java/security/InformationLeak.qll
+++ b/java/ql/lib/semmle/code/java/security/InformationLeak.qll
@@ -2,7 +2,7 @@
 
 import java
 import semmle.code.java.dataflow.DataFlow
-import semmle.code.java.dataflow.ExternalFlow
+private import semmle.code.java.dataflow.ExternalFlow
 import semmle.code.java.security.XSS
 
 /** CSV sink models representing methods not susceptible to XSS but outputing to an HTTP response body. */
diff --git a/java/ql/lib/semmle/code/java/security/LogInjection.qll b/java/ql/lib/semmle/code/java/security/LogInjection.qll
index f446a7edee8..55e4a785d4b 100644
--- a/java/ql/lib/semmle/code/java/security/LogInjection.qll
+++ b/java/ql/lib/semmle/code/java/security/LogInjection.qll
@@ -2,7 +2,7 @@
 
 import java
 import semmle.code.java.dataflow.DataFlow
-import semmle.code.java.dataflow.ExternalFlow
+private import semmle.code.java.dataflow.ExternalFlow
 
 /** A data flow sink for unvalidated user input that is used to log messages. */
 abstract class LogInjectionSink extends DataFlow::Node { }
diff --git a/java/ql/lib/semmle/code/java/security/QueryInjection.qll b/java/ql/lib/semmle/code/java/security/QueryInjection.qll
index f4fe51969b9..ed81c12074f 100644
--- a/java/ql/lib/semmle/code/java/security/QueryInjection.qll
+++ b/java/ql/lib/semmle/code/java/security/QueryInjection.qll
@@ -4,7 +4,7 @@ import java
 import semmle.code.java.dataflow.DataFlow
 import semmle.code.java.frameworks.javaee.Persistence
 private import semmle.code.java.frameworks.MyBatis
-import semmle.code.java.dataflow.ExternalFlow
+private import semmle.code.java.dataflow.ExternalFlow
 
 /** A sink for database query language injection vulnerabilities. */
 abstract class QueryInjectionSink extends DataFlow::Node { }
diff --git a/java/ql/lib/semmle/code/java/security/SensitiveLoggingQuery.qll b/java/ql/lib/semmle/code/java/security/SensitiveLoggingQuery.qll
index df0db54f159..7c87cec5aa5 100644
--- a/java/ql/lib/semmle/code/java/security/SensitiveLoggingQuery.qll
+++ b/java/ql/lib/semmle/code/java/security/SensitiveLoggingQuery.qll
@@ -1,7 +1,7 @@
 /** Provides configurations for sensitive logging queries. */
 
 import java
-import semmle.code.java.dataflow.ExternalFlow
+private import semmle.code.java.dataflow.ExternalFlow
 import semmle.code.java.dataflow.TaintTracking
 import semmle.code.java.security.SensitiveActions
 import DataFlow
diff --git a/java/ql/lib/semmle/code/java/security/UrlRedirect.qll b/java/ql/lib/semmle/code/java/security/UrlRedirect.qll
index 254ea873fcc..f4fc862ab53 100644
--- a/java/ql/lib/semmle/code/java/security/UrlRedirect.qll
+++ b/java/ql/lib/semmle/code/java/security/UrlRedirect.qll
@@ -2,7 +2,7 @@
 
 import java
 import semmle.code.java.dataflow.DataFlow
-import semmle.code.java.dataflow.ExternalFlow
+private import semmle.code.java.dataflow.ExternalFlow
 import semmle.code.java.frameworks.Servlets
 import semmle.code.java.frameworks.ApacheHttp
 private import semmle.code.java.frameworks.JaxWS
diff --git a/java/ql/lib/semmle/code/java/security/XPath.qll b/java/ql/lib/semmle/code/java/security/XPath.qll
index 374fbcdbebe..4678d7572c7 100644
--- a/java/ql/lib/semmle/code/java/security/XPath.qll
+++ b/java/ql/lib/semmle/code/java/security/XPath.qll
@@ -2,7 +2,7 @@
 
 import java
 import semmle.code.java.dataflow.DataFlow
-import semmle.code.java.dataflow.ExternalFlow
+private import semmle.code.java.dataflow.ExternalFlow
 
 /**
  * A sink that represents a method that interprets XPath expressions.
diff --git a/java/ql/lib/semmle/code/java/security/XSS.qll b/java/ql/lib/semmle/code/java/security/XSS.qll
index 23bda5b9964..fa94fe09cac 100644
--- a/java/ql/lib/semmle/code/java/security/XSS.qll
+++ b/java/ql/lib/semmle/code/java/security/XSS.qll
@@ -8,7 +8,7 @@ import semmle.code.java.frameworks.spring.SpringHttp
 import semmle.code.java.frameworks.javaee.jsf.JSFRenderer
 import semmle.code.java.dataflow.DataFlow
 import semmle.code.java.dataflow.TaintTracking2
-import semmle.code.java.dataflow.ExternalFlow
+private import semmle.code.java.dataflow.ExternalFlow
 
 /** A sink that represent a method that outputs data without applying contextual output encoding. */
 abstract class XssSink extends DataFlow::Node { }
diff --git a/java/ql/lib/semmle/code/java/security/XsltInjection.qll b/java/ql/lib/semmle/code/java/security/XsltInjection.qll
index db96879181c..84a2f79a06a 100644
--- a/java/ql/lib/semmle/code/java/security/XsltInjection.qll
+++ b/java/ql/lib/semmle/code/java/security/XsltInjection.qll
@@ -2,7 +2,7 @@
 
 import java
 import semmle.code.java.dataflow.DataFlow
-import semmle.code.java.dataflow.ExternalFlow
+private import semmle.code.java.dataflow.ExternalFlow
 
 /**
  * A data flow sink for unvalidated user input that is used in XSLT transformation.
diff --git a/java/ql/src/experimental/Security/CWE/CWE-200/AndroidFileIntentSink.qll b/java/ql/src/experimental/Security/CWE/CWE-200/AndroidFileIntentSink.qll
index b6d799c9266..e8795a25431 100644
--- a/java/ql/src/experimental/Security/CWE/CWE-200/AndroidFileIntentSink.qll
+++ b/java/ql/src/experimental/Security/CWE/CWE-200/AndroidFileIntentSink.qll
@@ -2,7 +2,7 @@
 
 import java
 import semmle.code.java.dataflow.DataFlow
-import semmle.code.java.dataflow.ExternalFlow
+private import semmle.code.java.dataflow.ExternalFlow
 import semmle.code.java.frameworks.android.Android
 import semmle.code.java.frameworks.android.Intent
 
diff --git a/java/ql/src/experimental/Security/CWE/CWE-400/ThreadResourceAbuse.qll b/java/ql/src/experimental/Security/CWE/CWE-400/ThreadResourceAbuse.qll
index b44ffa3b812..4f654374b17 100644
--- a/java/ql/src/experimental/Security/CWE/CWE-400/ThreadResourceAbuse.qll
+++ b/java/ql/src/experimental/Security/CWE/CWE-400/ThreadResourceAbuse.qll
@@ -2,7 +2,7 @@
 
 import java
 import semmle.code.java.dataflow.DataFlow
-import semmle.code.java.dataflow.ExternalFlow
+private import semmle.code.java.dataflow.ExternalFlow
 import semmle.code.java.dataflow.FlowSteps
 
 /** `java.lang.Math` data model for value comparison in the new CSV format. */