diff --git a/lib/des/des.c b/lib/des/des.c
index 4762a4b43..6c4d5e6a2 100644
--- a/lib/des/des.c
+++ b/lib/des/des.c
@@ -559,7 +559,7 @@ DES_cbc_cksum(const unsigned char *input, DES_cblock *output,
 	      long length, DES_key_schedule *ks, DES_cblock *iv)
 {
     uint32_t uiv[2];
-    uint32_t u[2];
+    uint32_t u[2] = { 0, 0 };
 
     load(*iv, uiv);