diff --git a/dlls/ole32/stg_prop.c b/dlls/ole32/stg_prop.c
index b3362bc21de..f887d10c0cf 100644
--- a/dlls/ole32/stg_prop.c
+++ b/dlls/ole32/stg_prop.c
@@ -1314,6 +1314,13 @@ static HRESULT PropertyStorage_ReadFromStream(PropertyStorage_impl *This)
     hr = PropertyStorage_ReadFmtIdOffsetFromStream(This->stm, &fmtOffset);
     if (FAILED(hr))
         goto end;
+    if (!IsEqualGUID(&fmtOffset.fmtid, &FMTID_DocSummaryInformation) &&
+        !IsEqualGUID(&fmtOffset.fmtid, &FMTID_SummaryInformation))
+    {
+        WARN("not reading unknown fmtid %s\n", debugstr_guid(&fmtOffset.fmtid));
+        hr = S_FALSE;
+        goto end;
+    }
     if (fmtOffset.dwOffset > stat.cbSize.u.LowPart)
     {
         WARN("invalid offset %d (stream length is %d)\n", fmtOffset.dwOffset,
diff --git a/dlls/ole32/tests/stg_prop.c b/dlls/ole32/tests/stg_prop.c
index 4e5fde74745..dff3361bdc6 100644
--- a/dlls/ole32/tests/stg_prop.c
+++ b/dlls/ole32/tests/stg_prop.c
@@ -333,7 +333,6 @@ static void testProps(void)
 
     hr = IPropertySetStorage_Open(propSetStorage, &anyOldGuid,
      STGM_READWRITE | STGM_SHARE_EXCLUSIVE, &propertyStorage);
-    todo_wine
     ok(hr == S_OK, "IPropertySetStorage_Open failed: 0x%08x\n", hr);
 
     spec.ulKind = PRSPEC_PROPID;