diff --git a/crypto/modes/cbc128.c b/crypto/modes/cbc128.c
index 9ac9299f65..86dd781c55 100644
--- a/crypto/modes/cbc128.c
+++ b/crypto/modes/cbc128.c
@@ -69,7 +69,8 @@ void CRYPTO_cbc128_encrypt(const unsigned char *in, unsigned char *out,
         in += 16;
         out += 16;
     }
-    memcpy(ivec, iv, 16);
+    if (ivec != iv)
+        memcpy(ivec, iv, 16);
 }
 
 void CRYPTO_cbc128_decrypt(const unsigned char *in, unsigned char *out,