diff --git a/netwerk/base/nsStandardURL.cpp b/netwerk/base/nsStandardURL.cpp
index 23bcb9d713e..f1ce9e203c7 100644
--- a/netwerk/base/nsStandardURL.cpp
+++ b/netwerk/base/nsStandardURL.cpp
@@ -3730,6 +3730,10 @@ bool nsStandardURL::Deserialize(const URIParams& aParams) {
   NS_ENSURE_TRUE(isSubSegment(mQuery, mPath), false);
   NS_ENSURE_TRUE(isSubSegment(mRef, mPath), false);
 
+  if (mAuthority.mLen >= 0 && mPath.mLen >= 0) {
+    NS_ENSURE_TRUE(mPath.mPos == mAuthority.mPos + mAuthority.mLen, false);
+  }
+
   if (!IsValid()) {
     return false;
   }
diff --git a/netwerk/base/nsStandardURL.h b/netwerk/base/nsStandardURL.h
index 3049cf6dd6f..79760da0268 100644
--- a/netwerk/base/nsStandardURL.h
+++ b/netwerk/base/nsStandardURL.h
@@ -412,6 +412,9 @@ class nsStandardURL : public nsIFileURL,
     }
 
     [[nodiscard]] NS_IMETHOD Finalize(nsIURI** aURI) override {
+      if (!BaseURIMutator<T>::mURI) {
+        return NS_ERROR_NULL_POINTER;
+      }
       BaseURIMutator<T>::mURI.forget(aURI);
       return NS_OK;
     }