diff --git a/src/core/qgscoordinatetransform.cpp b/src/core/qgscoordinatetransform.cpp
index d07fc2953b1..fd08c905018 100644
--- a/src/core/qgscoordinatetransform.cpp
+++ b/src/core/qgscoordinatetransform.cpp
@@ -426,6 +426,12 @@ QgsRectangle QgsCoordinateTransform::transformBoundingBox( const QgsRectangle &r
     }
   }
 
+  if ( bb_rect.isNull() )
+  {
+    // something bad happened when reprojecting the filter rect... no finite points were left!
+    throw QgsCsException( QObject::tr( "Could not transform bounding box to target CRS" ) );
+  }
+
   if ( handle180Crossover )
   {
     //subtract temporary addition of 360 degrees from longitudes
diff --git a/tests/src/core/testqgscoordinatetransform.cpp b/tests/src/core/testqgscoordinatetransform.cpp
index b0e28bcee4f..b9d554b4230 100644
--- a/tests/src/core/testqgscoordinatetransform.cpp
+++ b/tests/src/core/testqgscoordinatetransform.cpp
@@ -19,6 +19,7 @@
 #include "qgsrectangle.h"
 #include <QObject>
 #include "qgstest.h"
+#include "qgsexception.h"
 
 class TestQgsCoordinateTransform: public QObject
 {
@@ -204,6 +205,20 @@ void TestQgsCoordinateTransform::transformBoundingBox()
   QGSCOMPARENEAR( resultRect.yMinimum(), expectedRect.yMinimum(), 0.001 );
   QGSCOMPARENEAR( resultRect.xMaximum(), expectedRect.xMaximum(), 0.001 );
   QGSCOMPARENEAR( resultRect.yMaximum(), expectedRect.yMaximum(), 0.001 );
+
+  // test transforming a bounding box, resulting in an invalid transform - exception must be thrown
+  tr = QgsCoordinateTransform( QgsCoordinateReferenceSystem( 4326 ), QgsCoordinateReferenceSystem( QStringLiteral( "EPSG:28356" ) ) );
+  QgsRectangle rect( -99999999999, 99999999999, -99999999998, 99999999998 );
+  bool errorObtained = false;
+  try
+  {
+    resultRect = tr.transformBoundingBox( rect );
+  }
+  catch ( QgsCsException & )
+  {
+    errorObtained = true;
+  }
+  QVERIFY( errorObtained );
 }
 
 QGSTEST_MAIN( TestQgsCoordinateTransform )