diff --git a/src/http_fetch.c b/src/http_fetch.c
index b501ab096..b030509d5 100644
--- a/src/http_fetch.c
+++ b/src/http_fetch.c
@@ -1100,7 +1100,7 @@ static int smp_fetch_hdr_ip(const struct arg *args, struct sample *smp, const ch
 				/* IPv4 address suffixed with ':' followed by a valid port number */
 				smp->data.type = SMP_T_IPV4;
 				break;
-			} else if (temp->area[0] == '[' && temp->area[smp->data.u.str.data-1] == ']') {
+			} else if (smp->data.u.str.data >= 2 && temp->area[0] == '[' && temp->area[smp->data.u.str.data-1] == ']') {
 				/* IPv6 address enclosed in square brackets */
 				temp->area[smp->data.u.str.data-1] = '\0';
 				if (inet_pton(AF_INET6, temp->area+1, &smp->data.u.ipv6)) {