diff --git a/firmware/lib/vboot_common.c b/firmware/lib/vboot_common.c
index e074d61..7878701 100644
--- a/firmware/lib/vboot_common.c
+++ b/firmware/lib/vboot_common.c
@@ -280,6 +280,7 @@
     /* Make sure advertised signature data sizes are sane. */
     if (block->key_block_size < sig->data_size) {
       VBDEBUG(("Signature calculated past end of the block\n"));
+      RSAPublicKeyFree(rsa);
       return VBOOT_KEY_BLOCK_INVALID;
     }