diff --git a/deno/src/utils.ts b/deno/src/utils.ts
index 6ce91c90..f4ae7c78 100644
--- a/deno/src/utils.ts
+++ b/deno/src/utils.ts
@@ -90,9 +90,8 @@ export async function shortHash(fileName: string): Promise<string> {
     count++;
   }
 
-  const parts = splitOnce(sub, ".", "right");
-  sub = parts[0];
-  let ext = parts.at(1);
+  sub = splitOnce(sub, ".", "right")[0];
+  let ext = splitOnce(fileName, ".", "right").at(1);
   ext = ext ? `.${ext}` : "";
 
   if (sub.length === 0) {
diff --git a/deno/tests/utils.test.ts b/deno/tests/utils.test.ts
index be4a424c..8bdb4c68 100644
--- a/deno/tests/utils.test.ts
+++ b/deno/tests/utils.test.ts
@@ -49,11 +49,15 @@ Deno.test("shortHash returns hashed filename for forbidden/long names", async ()
   const result = await shortHash("ThisIsUppercase.txt");
   assertMatch(result, /^#thisisuppercase_[a-f0-9]{5}\.txt$/);
   const result2 = await shortHash("file?name.txt");
-  assertMatch(result2, /^#file_[a-f0-9]{5}$/);
+  assertMatch(result2, /^#file_[a-f0-9]{5}.txt$/);
   const result3 = await shortHash("a".repeat(40));
   assertMatch(result3, /^#aaaaaaaaaaaaaaaaaaaa_[a-f0-9]{5}$/);
   const result4 = await shortHash("file<name.ts");
   assertMatch(result4, /^#file_name_[a-f0-9]{5}.ts$/);
+  const result5 = await shortHash(
+    "unstable_get_network_address.ts",
+  );
+  assertEquals(result5, "#unstable_get_network_b61b7.ts");
 });
 
 Deno.test("shortHash returns hashed filename for empty string", async () => {