diff --git a/winbuild/build_prepare.py b/winbuild/build_prepare.py
index 3cd841484..14f8d7ba0 100644
--- a/winbuild/build_prepare.py
+++ b/winbuild/build_prepare.py
@@ -474,7 +474,7 @@ def extract_dep(url, filename):
         with zipfile.ZipFile(file) as zf:
             for member in zf.namelist():
                 member_abspath = os.path.abspath(os.path.join(sources_dir, member))
-                member_prefix = os.path.commonprefix([sources_dir_abs, member_abspath])
+                member_prefix = os.path.commonpath([sources_dir_abs, member_abspath])
                 if sources_dir_abs != member_prefix:
                     raise RuntimeError("Attempted Path Traversal in Zip File")
             zf.extractall(sources_dir)
@@ -482,7 +482,7 @@ def extract_dep(url, filename):
         with tarfile.open(file, "r:gz") as tgz:
             for member in tgz.getmembers():
                 member_abspath = os.path.abspath(os.path.join(sources_dir, member.name))
-                member_prefix = os.path.commonprefix([sources_dir_abs, member_abspath])
+                member_prefix = os.path.commonpath([sources_dir_abs, member_abspath])
                 if sources_dir_abs != member_prefix:
                     raise RuntimeError("Attempted Path Traversal in Tar File")
             tgz.extractall(sources_dir)