diff --git a/src/apps/relay/dtls_listener.c b/src/apps/relay/dtls_listener.c
index 99e2e048..7fe39636 100644
--- a/src/apps/relay/dtls_listener.c
+++ b/src/apps/relay/dtls_listener.c
@@ -691,7 +691,7 @@ start_udp_cycle:
 #endif
     static char buffer[65535];
     uint32_t errcode = 0;
-    ioa_addr orig_addr;
+    ioa_addr orig_addr = {0};
     int ttl = 0;
     int tos = 0;
     socklen_t slen = server->slen0;
diff --git a/src/client/ns_turn_msg.c b/src/client/ns_turn_msg.c
index 00d4db61..4b640c49 100644
--- a/src/client/ns_turn_msg.c
+++ b/src/client/ns_turn_msg.c
@@ -1766,7 +1766,7 @@ void print_bin_func(const char *name, size_t len, const void *s, const char *fun
 
 bool stun_attr_add_integrity_str(turn_credential_type ct, uint8_t *buf, size_t *len, hmackey_t key, password_t pwd,
                                  SHATYPE shatype) {
-  uint8_t hmac[MAXSHASIZE];
+  uint8_t hmac[MAXSHASIZE] = {0};
 
   unsigned int shasize;
 
diff --git a/src/server/ns_turn_server.c b/src/server/ns_turn_server.c
index 5bb45ac2..2dc597b5 100644
--- a/src/server/ns_turn_server.c
+++ b/src/server/ns_turn_server.c
@@ -3553,7 +3553,7 @@ static int handle_turn_command(turn_turnserver *server, ts_ur_super_session *ss,
     return -1;
   }
 
-  uint16_t unknown_attrs[MAX_NUMBER_OF_UNKNOWN_ATTRS];
+  uint16_t unknown_attrs[MAX_NUMBER_OF_UNKNOWN_ATTRS] = {0};
   uint16_t ua_num = 0;
   const uint16_t method =
       stun_get_method_str(ioa_network_buffer_data(in_buffer->nbh), ioa_network_buffer_get_size(in_buffer->nbh));
@@ -3946,7 +3946,7 @@ static int handle_old_stun_command(turn_turnserver *server, ts_ur_super_session
   const uint8_t *reason = NULL;
   int no_response = 0;
 
-  uint16_t unknown_attrs[MAX_NUMBER_OF_UNKNOWN_ATTRS];
+  uint16_t unknown_attrs[MAX_NUMBER_OF_UNKNOWN_ATTRS] = {0};
   uint16_t ua_num = 0;
   const uint16_t method =
       stun_get_method_str(ioa_network_buffer_data(in_buffer->nbh), ioa_network_buffer_get_size(in_buffer->nbh));