diff --git a/tests/Pipfile b/tests/Pipfile
index fdfb7e3737b..8957f27fd5b 100644
--- a/tests/Pipfile
+++ b/tests/Pipfile
@@ -39,5 +39,11 @@ microserver = ">=1.0.6"
 jsonschema = "*"
 python-jose = "*"
 
+# The latest version of Werkzeug (2.1.0) breaks httpbin because it removes
+# deprecated function `BaseResponse` that httpbin directly or indirectly
+# depends upon. Pinning Wekrzeug for now until httpbin or its dependencies is
+# updated for the changed API.
+Werkzeug = "==2.0.3"
+
 [requires]
 python_version = "3"
diff --git a/tests/bootstrap.py b/tests/bootstrap.py
index 3d9e437661f..639c2fa00ac 100755
--- a/tests/bootstrap.py
+++ b/tests/bootstrap.py
@@ -37,7 +37,13 @@
     "dnslib",
     "httpbin",
     "gunicorn",
-    "traffic-replay"  # this should install TRLib, MicroServer, MicroDNS, Traffic-Replay
+    "traffic-replay",  # this should install TRLib, MicroServer, MicroDNS, Traffic-Replay
+
+    # The latest version of Werkzeug (2.1.0) breaks httpbin because it removes
+    # deprecated function `BaseResponse` that httpbin directly or indirectly
+    # depends upon. Pinning Wekrzeug for now until httpbin or its dependencies
+    # is updated for the changed API.
+    "Werkzeug==2.0.3"
 ]