diff --git a/lib/dns/hmac_link.c b/lib/dns/hmac_link.c
index 464628db13..71d1b6a2b5 100644
--- a/lib/dns/hmac_link.c
+++ b/lib/dns/hmac_link.c
@@ -360,6 +360,7 @@ hmac_fromdns(isc_md_type_t type, dst_key_t *key, isc_buffer_t *data) {
 	if (r.length > (unsigned int)isc_md_type_get_block_size(type)) {
 		if (isc_md(type, r.base, r.length, hkey->key, &keylen)
 		    != ISC_R_SUCCESS) {
+			isc_mem_put(key->mctx, hkey, sizeof(dst_hmac_key_t));
 			return (DST_R_OPENSSLFAILURE);
 		}
 	} else {