diff --git a/programs/pkey/pk_encrypt.c b/programs/pkey/pk_encrypt.c
index aa202b0..149e7dd 100644
--- a/programs/pkey/pk_encrypt.c
+++ b/programs/pkey/pk_encrypt.c
@@ -136,6 +136,7 @@
     printf( "\n  . Done (created \"%s\")\n\n", "result-enc.txt" );
 
 exit:
+    entropy_free( &entropy );
 
 #if defined(POLARSSL_ERROR_C)
     polarssl_strerror( ret, (char *) buf, sizeof(buf) );