diff --git a/library/psa_crypto.c b/library/psa_crypto.c
index d8a9940..c58fdae 100644
--- a/library/psa_crypto.c
+++ b/library/psa_crypto.c
@@ -3392,7 +3392,7 @@
 {
     psa_status_t status = PSA_ERROR_CORRUPTION_DETECTED;
     uint8_t local_iv[PSA_CIPHER_IV_MAX_SIZE];
-    size_t default_iv_length;
+    size_t default_iv_length = 0;
 
     if (operation->id == 0) {
         status = PSA_ERROR_BAD_STATE;