diff --git a/taskcluster/scripts/misc/unpack-sdk.py b/taskcluster/scripts/misc/unpack-sdk.py
index e17f98d6578e..30021d1d4fd2 100644
--- a/taskcluster/scripts/misc/unpack-sdk.py
+++ b/taskcluster/scripts/misc/unpack-sdk.py
@@ -11,34 +11,11 @@ import tempfile
 from io import BytesIO
 from urllib.request import urlopen
 
-from mozpack.macpkg import Pbzx, uncpio, unxar
+from macpkg import Pbzx, uncpio, unxar
 
 
-def unpack_sdk(url, sha512, extract_prefix, out_dir="."):
-    if "MOZ_AUTOMATION" in os.environ:
-        url = f"http://taskcluster/tooltool.mozilla-releng.net/sha512/{sha512}"
-    with tempfile.TemporaryFile() as pkg:
-        hash = hashlib.sha512()
-        for attempt in range(3):
-            if attempt != 0:
-                print(f"Failed to download from {url}. Retrying", file=sys.stderr)
-
-            with urlopen(url) as fh:
-                # Equivalent to shutil.copyfileobj, but computes sha512 at the same time.
-                while True:
-                    buf = fh.read(1024 * 1024)
-                    if not buf:
-                        break
-                    hash.update(buf)
-                    pkg.write(buf)
-            digest = hash.hexdigest()
-            if digest == sha512:
-                break
-        else:
-            raise Exception(f"(actual) {digest} != (expected) {sha512}")
-
-        pkg.seek(0, os.SEEK_SET)
-
+def unpack_sdk(filename, extract_prefix, out_dir="."):
+    with open(filename, "rb") as pkg:
         for name, content in unxar(pkg):
             if name in ("Payload", "Content"):
                 extract_payload(content, extract_prefix, out_dir)
