diff --git a/chart2/source/controller/main/ChartController_Window.cxx b/chart2/source/controller/main/ChartController_Window.cxx
index bb9e58009d50..86bdf100a73e 100644
--- a/chart2/source/controller/main/ChartController_Window.cxx
+++ b/chart2/source/controller/main/ChartController_Window.cxx
@@ -2076,7 +2076,7 @@ void ChartController::sendPopupRequest(std::u16string_view rCID, tools::Rectangl
 
     // Get dimension index from CID
     size_t nStartPos = rCID.rfind('.');
-    nStartPos++;
+    nStartPos = (nStartPos == std::u16string_view::npos) ? 0 : (nStartPos + 1);
     sal_Int32 nEndPos = rCID.size();
     std::u16string_view sDimensionIndex = rCID.substr(nStartPos, nEndPos - nStartPos);
     sal_Int32 nDimensionIndex = o3tl::toInt32(sDimensionIndex);
diff --git a/sc/source/core/tool/interpr2.cxx b/sc/source/core/tool/interpr2.cxx
index 2d87abed4789..f1443b9c5109 100644
--- a/sc/source/core/tool/interpr2.cxx
+++ b/sc/source/core/tool/interpr2.cxx
@@ -3602,8 +3602,9 @@ void ScInterpreter::ScGetPivotData()
         aFilters.resize(nFilterCount);
 
         sal_uInt16 i = nFilterCount;
-        while (i-- > 0)
+        while (i > 0)
         {
+            --i;
             /* TODO: also, in case of numeric the entire filter match should
              * not be on a (even if locale independent) formatted string down
              * below in pDPObj->GetPivotData(). */