diff --git a/cfy_manager/tests/test_certificates.py b/cfy_manager/tests/test_certificates.py
index 219a32807..2f94ba67d 100644
--- a/cfy_manager/tests/test_certificates.py
+++ b/cfy_manager/tests/test_certificates.py
@@ -77,7 +77,7 @@ def ca_cert(tmpdir):
 
     key = rsa.generate_private_key(
         public_exponent=65537,
-        key_size=512,  # no need for a big key in tests
+        key_size=1024,  # cryptography 42.0.3/changelog/3.3
     )
     key_password = 'key_password1'
 
@@ -289,7 +289,7 @@ def test_remove_key_encryption(tmpdir, ca_cert):
 
     key = rsa.generate_private_key(
         public_exponent=65537,
-        key_size=512,
+        key_size=1024,
     )
     with open(source_key, 'wb') as key_file:
         key_pem = key.private_bytes(