diff --git a/tox.ini b/tox.ini
index 5fa6fc1..3e65358 100644
--- a/tox.ini
+++ b/tox.ini
@@ -16,6 +16,7 @@ deps =
     pyasn1-modules
     pymox < 1.2
     pytest-cov
+    pytest<8
     requests-mock
     rsa
     sortedcontainers