--- src/libs/zbxsysinfo/common/net.c	2018-08-28 18:33:58.495308195 +0300
+++ src/libs/zbxsysinfo/common/net.c.with_padding	2018-08-28 18:27:58.202092551 +0300
@@ -189,7 +189,14 @@
 	struct in_addr		inaddr;
 #ifndef _WINDOWS
 #ifdef HAVE_RES_NINIT
-	struct __res_state	res_state_local;
+	/* It seems that on some AIX systems without updates installed res_ninit() can corrupt */
+	/* stack causing a crash (see ZBX-14559). Adding some padding bytes helps to avoid crash. */
+	struct {
+		struct __res_state	res_state;
+#ifdef _AIX
+		char padding[128];
+#endif
+	} rs;
 #else	/* thread-unsafe resolver API */
 	int			saved_nscount = 0, saved_retrans, saved_retry;
 	unsigned long		saved_options;
@@ -470,8 +477,8 @@
 	}
 #else	/* not _WINDOWS */
 #ifdef HAVE_RES_NINIT
-	memset(&res_state_local, 0, sizeof(res_state_local));
-	if (-1 == res_ninit(&res_state_local))	/* initialize always, settings might have changed */
+	memset(&rs.res_state, 0, sizeof(rs.res_state));
+	if (-1 == res_ninit(&rs.res_state))	/* initialize always, settings might have changed */
 #else
 	if (-1 == res_init())	/* initialize always, settings might have changed */
 #endif
@@ -481,7 +488,7 @@
 	}
 
 #ifdef HAVE_RES_NINIT
-	if (-1 == (res = res_nmkquery(&res_state_local, QUERY, zone, C_IN, type, NULL, 0, NULL, buf, sizeof(buf))))
+	if (-1 == (res = res_nmkquery(&rs.res_state, QUERY, zone, C_IN, type, NULL, 0, NULL, buf, sizeof(buf))))
 #else
 	if (-1 == (res = res_mkquery(QUERY, zone, C_IN, type, NULL, 0, NULL, buf, sizeof(buf))))
 #endif
@@ -499,10 +506,10 @@
 		}
 
 #ifdef HAVE_RES_NINIT
-		res_state_local.nsaddr_list[0].sin_addr = inaddr;
-		res_state_local.nsaddr_list[0].sin_family = AF_INET;
-		res_state_local.nsaddr_list[0].sin_port = htons(ZBX_DEFAULT_DNS_PORT);
-		res_state_local.nscount = 1;
+		rs.res_state.nsaddr_list[0].sin_addr = inaddr;
+		rs.res_state.nsaddr_list[0].sin_family = AF_INET;
+		rs.res_state.nsaddr_list[0].sin_port = htons(ZBX_DEFAULT_DNS_PORT);
+		rs.res_state.nscount = 1;
 #else	/* thread-unsafe resolver API */
 		memcpy(&saved_ns, &(_res.nsaddr_list[0]), sizeof(struct sockaddr_in));
 		saved_nscount = _res.nscount;
@@ -516,16 +523,16 @@
 
 #ifdef HAVE_RES_NINIT
 	if (0 != use_tcp)
-		res_state_local.options |= RES_USEVC;
+		rs.res_state.options |= RES_USEVC;
 
-	res_state_local.retrans = retrans;
-	res_state_local.retry = retry;
+	rs.res_state.retrans = retrans;
+	rs.res_state.retry = retry;
 
-	res = res_nsend(&res_state_local, buf, res, answer.buffer, sizeof(answer.buffer));
+	res = res_nsend(&rs.res_state, buf, res, answer.buffer, sizeof(answer.buffer));
 #	if HAVE_RES_NDESTROY
-	res_ndestroy(&res_state_local);
+	res_ndestroy(&rs.res_state);
 #	else
-	res_nclose(&res_state_local);
+	res_nclose(&rs.res_state);
 #	endif
 #else	/* thread-unsafe resolver API */
 	saved_options = _res.options;