diff --git a/dlls/windowscodecs/tgaformat.c b/dlls/windowscodecs/tgaformat.c
index cd615c71c80..ac57e545ed5 100644
--- a/dlls/windowscodecs/tgaformat.c
+++ b/dlls/windowscodecs/tgaformat.c
@@ -405,6 +405,8 @@ static HRESULT WINAPI TgaDecoder_GetThumbnail(IWICBitmapDecoder *iface,
 static HRESULT WINAPI TgaDecoder_GetFrameCount(IWICBitmapDecoder *iface,
     UINT *pCount)
 {
+    if (!pCount) return E_INVALIDARG;
+
     *pCount = 1;
     return S_OK;
 }