diff --git a/bundler/spec/install/gemfile/sources_spec.rb b/bundler/spec/install/gemfile/sources_spec.rb
index 4957ef70be2c..c72a2b982a99 100644
--- a/bundler/spec/install/gemfile/sources_spec.rb
+++ b/bundler/spec/install/gemfile/sources_spec.rb
@@ -1273,4 +1273,41 @@
       expect(the_bundle).to include_gems("missing_dep 1.0.0", source: "remote2")
     end
   end
+
+  context "when a git gem has a transitive dependency that does not exist in the git source" do
+    before do
+      build_repo2 do
+        build_gem "missing_dep", "1.0.0"
+        build_gem "foo", "1.0.0"
+      end
+
+      build_git "parent_gem", "1.0.0", path: lib_path("parent_gem") do |s|
+        s.add_dependency "missing_dep"
+      end
+
+      gemfile <<-G
+        source "https://gem.repo2"
+
+        gem "foo"
+
+        gem "parent_gem", git: "#{lib_path("parent_gem")}"
+      G
+
+      bundle :install, artifice: "compact_index"
+    end
+
+    it "falls back to the default rubygems source for that dependency when updating" do
+      build_repo2 do
+        build_gem "foo", "2.0.0"
+      end
+
+      system_gems []
+
+      bundle "update foo", artifice: "compact_index"
+
+      expect(the_bundle).to include_gems("parent_gem 1.0.0", "missing_dep 1.0.0", "foo 2.0.0")
+      expect(the_bundle).to include_gems("parent_gem 1.0.0", source: "git@#{lib_path("parent_gem")}")
+      expect(the_bundle).to include_gems("missing_dep 1.0.0", source: "remote2")
+    end
+  end
 end