A heap-based buffer overflow exists in Visual Studio and .NET that allows an unauthorized attacker to execute code over a network. The issue occurs in the Microsoft.DiaSymReader.Native components when initializing the native reader with a crafted Portable PDB containing an `EmbeddedSource` record with parent RID 0, which triggers an out-of-bounds write. This initialization can be reached via the Windows runtime native stack-trace reader through its native-reader fallback.