diff --git a/tox.ini b/tox.ini
index fcd3563b2..aba94d79d 100644
--- a/tox.ini
+++ b/tox.ini
@@ -12,10 +12,11 @@ deps =
     -rtests/requirements.txt
     # mitmproxy does not support PyPy
     # mitmproxy does not support Windows when running Python < 3.7
-    # Python 3.9+ requires https://github.com/mitmproxy/mitmproxy/commit/8e5e43de24c9bc93092b63efc67fbec029a9e7fe
+    # Python 3.9+ requires mitmproxy >= 5.3.0
     # mitmproxy >= 5.3.0 requires h2 >= 4.0, Twisted 21.2 requires h2 < 4.0
     #mitmproxy >= 5.3.0; python_version >= '3.9' and implementation_name != 'pypy'
-    mitmproxy >= 4.0.4; python_version >= '3.7' and python_version < '3.9' and implementation_name != 'pypy'
+    # The tests hang with mitmproxy 8.0.0: https://github.com/scrapy/scrapy/issues/5454
+    mitmproxy >= 4.0.4, < 8; python_version >= '3.7' and python_version < '3.9' and implementation_name != 'pypy'
     mitmproxy >= 4.0.4, < 5; python_version >= '3.6' and python_version < '3.7' and platform_system != 'Windows' and implementation_name != 'pypy'
     # newer markupsafe is incompatible with deps of old mitmproxy (which we get on Python 3.7 and lower)
     markupsafe < 2.1.0; python_version >= '3.6' and python_version < '3.8' and implementation_name != 'pypy'