diff --git a/cpp/ql/lib/semmle/code/cpp/security/PrivateData.qll b/cpp/ql/lib/semmle/code/cpp/security/PrivateData.qll
index 3ca81e614ad..04bd031d308 100644
--- a/cpp/ql/lib/semmle/code/cpp/security/PrivateData.qll
+++ b/cpp/ql/lib/semmle/code/cpp/security/PrivateData.qll
@@ -1,16 +1,16 @@
 /**
- * Provides classes and predicates for identifying private data and methods for security.
+ * Provides classes for heuristically identifying variables and functions that
+ * might contain or return sensitive private data.
  *
- * 'Private' data in general is anything that would compromise user privacy if exposed. This
- * library tries to guess where private data may either be stored in a variable or produced by a
- * method.
+ * 'Private' data in general is anything that would compromise user privacy if
+ * exposed. This library tries to guess where private data may either be stored
+ * in a variable or returned by a function call.
  *
- * This library is not concerned with credentials. See `SensitiveActions` for expressions related
- * to credentials.
+ * This library is not concerned with credentials. See `SensitiveExprs.qll` for
+ * expressions related to credentials.
  */
 
-import csharp
-import semmle.code.csharp.frameworks.system.windows.Forms
+import cpp
 
 /** A string for `match` that identifies strings that look like they represent private data. */
 private string privateNames() {
@@ -32,35 +32,32 @@ private string privateNames() {
     ]
 }
 
-/** An expression that might contain private data. */
-abstract class PrivateDataExpr extends Expr { }
-
-/** A method call that might produce private data. */
-class PrivateMethodCall extends PrivateDataExpr, MethodCall {
-  PrivateMethodCall() {
-    exists(string s | this.getTarget().getName().toLowerCase() = s | s.matches(privateNames()))
+/**
+ * A variable that might contain sensitive private information.
+ */
+class PrivateDataVariable extends Variable {
+  PrivateDataVariable() {
+    this.getName().toLowerCase().matches(privateNames()) and
+    not this.getUnspecifiedType() instanceof IntegralType
   }
 }
 
-/** An indexer access that might produce private data. */
-class PrivateIndexerAccess extends PrivateDataExpr, IndexerAccess {
-  PrivateIndexerAccess() {
-    exists(string s | this.getAnIndex().getValue().toLowerCase() = s | s.matches(privateNames()))
+/**
+ * A function that might return sensitive private information.
+ */
+class PrivateDataFunction extends Function {
+  PrivateDataFunction() {
+    this.getName().toLowerCase().matches(privateNames()) and
+    not this.getUnspecifiedType() instanceof IntegralType
   }
 }
 
-/** An access to a variable that might contain private data. */
-class PrivateVariableAccess extends PrivateDataExpr, VariableAccess {
-  PrivateVariableAccess() {
-    exists(string s | this.getTarget().getName().toLowerCase() = s | s.matches(privateNames()))
-  }
-}
-
-/** Reading the text property of a control that might contain private data. */
-class PrivateControlAccess extends PrivateDataExpr {
-  PrivateControlAccess() {
-    exists(TextControl c |
-      this = c.getARead() and c.getName().toLowerCase().matches(privateNames())
-    )
+/**
+ * An expression whose value might be sensitive private information.
+ */
+class PrivateDataExpr extends Expr {
+  PrivateDataExpr() {
+    this.(VariableAccess).getTarget() instanceof PrivateDataVariable or
+    this.(FunctionCall).getTarget() instanceof PrivateDataFunction
   }
 }