[BUG] OpenSIPS 3.6.3 event_rabbitmq fails RabbitMQ auth: password missing

[kertor]

OpenSIPS version you are running

3.6.3~20251218~d5222226a-1 - with bug
3.5.5~20250519~7d163590b-1 - working correctly

Describe the bug

After upgrading OpenSIPS from 3.5.5 to 3.6.3, event_rabbitmq fails to authenticate to RabbitMQ using SASL PLAIN. A packet capture shows that in 3.6.3 the SASL PLAIN response contains the username but the password is missing (empty), which leads to:
ACCESS_REFUSED - Login was refused using authentication mechanism PLAIN
The same configuration and credentials work on 3.5.5.

Password contains only alnum in this reproduction.
No TLS.

To Reproduce

Using code:

########################################################################
loadmodule "event_rabbitmq.so"
########################################################################
modparam("event_rabbitmq", "heartbeat", 0)

and

if (!raise_event("E_REG_STAT", $avp(attr-name), $avp(attr-val))) xlog("L_ERR",  "[$route.name] Cannot raise E_REG_STAT event (tu=$tU@$td ci=$ci)\n");

and

startup_route {
    subscribe_event("E_REG_STAT", "rabbitmq:user:pass@192.168.100.100:5672/exchange=events.test.test?");
}

OpenSIPS 3.6.3 (fails)

SASL mechanism is PLAIN, but the response payload includes only the username and an empty password.

Relevant bytes:

... PLAIN .... 00 00 00 06 00 75 73 65 72 00 ...

Interpreting the PLAIN response as: 0x00 + "user" + 0x00 + "password"
gives:

"\0user\0"    (password is empty)

OpenSIPS 3.5.5 (works)

SASL PLAIN response includes both username and password.

Relevant bytes:

... PLAIN .... 00 00 00 0A 00 75 73 65 72 00 70 61 73 73 ...

Which corresponds to:

"\0user\0pass"

Expected behavior

OpenSIPS 3.6.3 send packets to remote RMQ server.
The same setup is working on 3.5.5

Relevant System Logs

/usr/sbin/opensips[2058704]: ERROR:event_rabbitmq:rmq_basic_server_publish: cannot connect to RabbitMQ server 192.168.100.100:5672
/usr/sbin/opensips[2058704]: ERROR:event_rabbitmq:rmq_process: cannot send message
/usr/sbin/opensips[2058704]: ERROR:event_rabbitmq:rmq_error: Logging in: server connection error 403, message: ACCESS_REFUSED - Login was refused using authentication mechanism PLAIN. For details see the broker logfile.

[kertor]

Thanks to @nikbyte , this patch is fixing the problem:

diff --git a/modules/event_rabbitmq/event_rabbitmq.c b/modules/event_rabbitmq/event_rabbitmq.c
index f2e6d73df..b071c5636 100644
--- a/modules/event_rabbitmq/event_rabbitmq.c
+++ b/modules/event_rabbitmq/event_rabbitmq.c
@@ -399,6 +399,8 @@ static evi_reply_sock* rmq_parse(str socket)
 				if (dupl_string(&tmp, begin, socket.s + i)) goto err;
 				param->conn.uri.user = tmp.s;
 				begin = socket.s + i + 1;
+				tmp.s = NULL; // avoid freeing it on next dupl_string()
+				tmp.len = 0;
 				param->conn.flags |= RMQ_PARAM_USER;
 				break;
 
@@ -427,6 +429,8 @@ static evi_reply_sock* rmq_parse(str socket)
 				if (dupl_string(&tmp, begin, socket.s + i) < 0)
 					goto err;
 				param->conn.uri.password = tmp.s;
+				tmp.s = NULL; // avoid freeing it on next dupl_string()
+				tmp.len = 0;
 				param->conn.flags |= RMQ_PARAM_PASS;
 				begin = socket.s + i + 1;
 				break;

Guys, could you please fix it in main code?