diff --git a/src/acl.h b/src/acl.h
index 05915b18..0f7c8e74 100644
--- a/src/acl.h
+++ b/src/acl.h
@@ -26,10 +26,10 @@
 #define BLACK_LIST 0
 #define WHITE_LIST 1
 
-#define MAX_TRIES  64
-#define MALICIOUS  32
-#define SUSPICIOUS 16
-#define BAD        4
+#define MAX_TRIES  128
+#define MALICIOUS  8
+#define SUSPICIOUS 4
+#define BAD        2
 #define MALFORMED  1
 
 int init_acl(const char *path);
diff --git a/src/jconf.h b/src/jconf.h
index 58d31650..c15d329e 100644
--- a/src/jconf.h
+++ b/src/jconf.h
@@ -27,6 +27,7 @@
 #define MAX_CONF_SIZE 128 * 1024
 #define MAX_DNS_NUM 4
 #define MAX_CONNECT_TIMEOUT 10
+#define MAX_REQUEST_TIMEOUT 60
 #define MIN_UDP_TIMEOUT 10
 
 #define TCP_ONLY     0
diff --git a/src/server.c b/src/server.c
index 87e49ab1..c1f7e010 100644
--- a/src/server.c
+++ b/src/server.c
@@ -233,6 +233,8 @@ parse_header_len(const char atyp, const char *data, size_t offset)
     } else if ((atyp & ADDRTYPE_MASK) == 4) {
         // IP V6
         len += sizeof(struct in6_addr);
+    } else {
+        return 0;
     }
     len += 2;
     return len;
@@ -262,6 +264,8 @@ is_header_complete(const buffer_t *buf)
     } else if ((atyp & ADDRTYPE_MASK) == 4) {
         // IP V6
         header_len += sizeof(struct in6_addr);
+    } else {
+        return 1;
     }
 
     // len of port
@@ -612,6 +616,25 @@ server_recv_cb(EV_P_ ev_io *w, int revents)
             // wait for more
             return;
         }
+
+        char *peer_name = get_peer_name(server->fd);
+        if (peer_name != NULL) {
+            if (check_block_list(peer_name, 0)) {
+                LOGE("block all requests from %s", peer_name);
+                close_and_free_remote(EV_A_ remote);
+                close_and_free_server(EV_A_ server);
+                return;
+            }
+            if (acl) {
+                if ((get_acl_mode() == BLACK_LIST && acl_match_host(peer_name) == 1)
+                        || (get_acl_mode() == WHITE_LIST && acl_match_host(peer_name) >= 0)) {
+                    LOGE("Access denied from %s", peer_name);
+                    close_and_free_remote(EV_A_ remote);
+                    close_and_free_server(EV_A_ server);
+                    return;
+                }
+            }
+        }
     } else {
         buf->len = r;
     }
@@ -730,7 +753,7 @@ server_recv_cb(EV_P_ ev_io *w, int revents)
             size_t header_len = parse_header_len(atyp, server->buf->array, offset);
             size_t len        = server->buf->len;
 
-            if (len < offset + header_len + ONETIMEAUTH_BYTES) {
+            if (header_len == 0 || len < offset + header_len + ONETIMEAUTH_BYTES) {
                 report_addr(server->fd, MALFORMED);
                 close_and_free_server(EV_A_ server);
                 return;
@@ -1335,10 +1358,12 @@ new_server(int fd, listen_ctx_t *listener)
         server->d_ctx = NULL;
     }
 
+    int request_timeout = min(MAX_REQUEST_TIMEOUT, listener->timeout);
+
     ev_io_init(&server->recv_ctx->io, server_recv_cb, fd, EV_READ);
     ev_io_init(&server->send_ctx->io, server_send_cb, fd, EV_WRITE);
     ev_timer_init(&server->recv_ctx->watcher, server_timeout_cb,
-                  min(MAX_CONNECT_TIMEOUT, listener->timeout), listener->timeout);
+                  request_timeout, listener->timeout);
 
     balloc(server->buf, BUF_SIZE);
     balloc(server->header_buf, BUF_SIZE);
@@ -1432,24 +1457,6 @@ accept_cb(EV_P_ ev_io *w, int revents)
         return;
     }
 
-    char *peer_name = get_peer_name(serverfd);
-
-    if (peer_name != NULL) {
-        if (check_block_list(peer_name, 0)) {
-            LOGE("block all requests from %s", peer_name);
-            close(serverfd);
-            return;
-        }
-        if (acl) {
-            if ((get_acl_mode() == BLACK_LIST && acl_match_host(peer_name) == 1)
-                || (get_acl_mode() == WHITE_LIST && acl_match_host(peer_name) >= 0)) {
-                LOGE("Access denied from %s", peer_name);
-                close(serverfd);
-                return;
-            }
-        }
-    }
-
     int opt = 1;
     setsockopt(serverfd, SOL_TCP, TCP_NODELAY, &opt, sizeof(opt));
 #ifdef SO_NOSIGPIPE