diff --git a/.github/workflows/go.yml b/.github/workflows/go.yml
index 93fc470..7d6b193 100644
--- a/.github/workflows/go.yml
+++ b/.github/workflows/go.yml
@@ -9,11 +9,11 @@ jobs:
     runs-on: ubuntu-20.04
     services:
       memcached:
-        image: memcached:1.6.19
+        image: memcached:1.6.37
         ports:
           - 11211:11211
       memcached2:
-        image: memcached:1.6.19
+        image: memcached:1.6.37
         ports:
           - 11212:11211
     steps:
diff --git a/plain_memcache_test.go b/plain_memcache_test.go
index a10750b..c6eb9b0 100644
--- a/plain_memcache_test.go
+++ b/plain_memcache_test.go
@@ -163,7 +163,7 @@ func TestPlainMemcache_LeaseSet_After_Delete__Rejected(t *testing.T) {
 	assert.Equal(t, nil, err)
 	assert.Equal(t, LeaseGetResponse{
 		Status: LeaseGetStatusLeaseGranted,
-		CAS:    cas + 1,
+		CAS:    cas + 2,
 	}, leaseGetResp)
 }