diff --git a/vcl/source/filter/png/PngImageReader.cxx b/vcl/source/filter/png/PngImageReader.cxx
index e3b3703c1cab..13c19feaf1ad 100644
--- a/vcl/source/filter/png/PngImageReader.cxx
+++ b/vcl/source/filter/png/PngImageReader.cxx
@@ -398,7 +398,7 @@ std::unique_ptr<sal_uInt8[]> getMsGifChunk(SvStream& rStream, sal_Int32* chunkSi
     bool ignoreCrc = utl::ConfigManager::IsFuzzing();
     for (;;)
     {
-        sal_uInt32 length, type, crc;
+        sal_uInt32 length(0), type(0), crc(0);
         rStream.ReadUInt32(length);
         rStream.ReadUInt32(type);
         if (!rStream.good())