diff --git a/boot/bootutil/src/encrypted.c b/boot/bootutil/src/encrypted.c
index e2e8211..c2c656d 100644
--- a/boot/bootutil/src/encrypted.c
+++ b/boot/bootutil/src/encrypted.c
@@ -325,7 +325,8 @@
 {
     size_t slot;
 
-    for(slot = 0; slot < BOOT_NUM_SLOTS; ++slot) {
+    for (slot = 0; slot < BOOT_NUM_SLOTS; ++slot) {
+        memset(&enc_state[slot].aes, 0, sizeof(enc_state[slot].aes));
         enc_state[slot].valid = 0;
     }
 }