MaxScale 2.5.5 crashes with signal 11

Hi,
I've just upgraded MaxScale from 2.4.12, which is working just fine and we're using it for a long time to 2.5.5. After updating configuration to new version MaxScale launched just fine, but as soon as I'm trying to use it it fails with signal11:

2020-10-30 14:53:44 alert : (2) (RW-Test) MaxScale 2.5.5 received fatal signal 11. Commit ID: 91c3b76195d0057ddbe572bbb8d17f6ac6b09d5e System name: Linux Release string: Ubuntu 18.04.5 LTS
2020-10-30 14:53:44 alert : (2) (RW-Test) Statement currently being classified: none/unknown
2020-10-30 14:53:44 notice : (2) (RW-Test) Stmt 5(1970-01-01 10:00:00): START TRANSACTION
2020-10-30 14:53:44 notice : (2) (RW-Test) Stmt 4(1970-01-01 10:00:00): SELECT XXXXXX
2020-10-30 14:53:44 notice : (2) (RW-Test) Stmt 3(1970-01-01 10:00:00): SELECT XXXXXX
2020-10-30 14:53:44 notice : (2) (RW-Test) Stmt 2(1970-01-01 10:00:00): COMMIT
2020-10-30 14:53:44 notice : (2) (RW-Test) Stmt 1(1970-01-01 10:00:00): START TRANSACTION
nm: /lib/x86_64-linux-gnu/libc.so.6: no symbols
2020-10-30 14:53:46 alert : (2) (RW-Test)
/usr/lib/x86_64-linux-gnu/maxscale/libmaxscale-common.so.1.0.0(_ZN7Session9QueryInfo20book_server_responseEP6SERVERb+0x33): /usr/include/c++/7/bits/vector.tcc:98
/usr/lib/x86_64-linux-gnu/maxscale/libmaxscale-common.so.1.0.0(_ZN7Session20book_server_responseEP6SERVERb+0xfe): server/core/session.cc:1109
/usr/lib/x86_64-linux-gnu/maxscale/libreadwritesplit.so(_ZN14RWSplitSession11clientReplyEP5GWBUFRKSt6vectorIPN8maxscale8EndpointESaIS5_EERKNS3_5ReplyE+0x196): server/modules/routing/readwritesplit/rwsplitsession.cc:606
/usr/lib/x86_64-linux-gnu/maxscale/libreadwritesplit.so(_ZN8maxscale6RouterI7RWSplit14RWSplitSessionE11clientReplyEP10mxs_routerP18mxs_router_sessionP5GWBUFRKSt6vectorIPNS_8EndpointESaISC_EERKNS_5ReplyE+0x2a): include/maxscale/router.hh:455
/usr/lib/x86_64-linux-gnu/maxscale/libmaxscale-common.so.1.0.0(_ZN15ServiceEndpoint11clientReplyEP5GWBUFRSt6vectorIPN8maxscale8EndpointESaIS5_EERKNS3_5ReplyE+0xae): server/core/service.cc:1848
/usr/lib/x86_64-linux-gnu/maxscale/libmaxscale-common.so.1.0.0(_ZN14ServerEndpoint11clientReplyEP5GWBUFRSt6vectorIPN8maxscale8EndpointESaIS5_EERKNS3_5ReplyE+0xbb): server/core/server.cc:981 (discriminator 2)
/usr/lib/x86_64-linux-gnu/maxscale/libmariadbclient.so(_ZN24MariaDBBackendConnection11normal_readEv+0x51d): server/modules/protocol/MariaDB/mariadb_backend.cc:828
/usr/lib/x86_64-linux-gnu/maxscale/libmaxscale-common.so.1.0.0(_ZN3DCB14process_eventsEj+0x6c): server/core/dcb.cc:1291
/usr/lib/x86_64-linux-gnu/maxscale/libmaxscale-common.so.1.0.0(_ZN3DCB13event_handlerEPS_j+0x21): server/core/dcb.cc:1350
/usr/lib/x86_64-linux-gnu/maxscale/libmaxscale-common.so.1.0.0(_ZN7maxbase6Worker15poll_waiteventsEv+0x1ce): maxutils/maxbase/src/worker.cc:879
/usr/lib/x86_64-linux-gnu/maxscale/libmaxscale-common.so.1.0.0(_ZN7maxbase6Worker3runEPNS_9SemaphoreE+0x53): maxutils/maxbase/src/worker.cc:574
/usr/lib/x86_64-linux-gnu/libstdc++.so.6(+0xbd6df): ??:?
/lib/x86_64-linux-gnu/libpthread.so.0(+0x76db): ??:?
/lib/x86_64-linux-gnu/libc.so.6(clone+0x3f): ??:0

Configuration:

[maxscale]

threads=auto

retain_last_statements=5

dump_last_statements=on_error

admin_secure_gui=false

admin_host=10.22.20.1

query_retries=3

[GaleraMonitorTest]

type=monitor

module=galeramon

servers=node1-test,node2-test,node3-test

user=root

password=root

monitor_interval=1000

disable_master_failback=true

available_when_donor=true

[RW-Test]

type=service

router=readwritesplit

servers=node1-test,node2-test,node3-test

user=root

password=root

max_slave_connections=100%

connection_keepalive=30

master_failure_mode=fail_on_write

master_accept_reads=true

disable_sescmd_history=true

enable_root_user=true

[RWlistener-Test]

type=listener

service=RW-Test

protocol=mariadbclient

address=10.22.20.1

port=3308

[node1-test]

type=server

address=10.22.23.201

port=3306

protocol=mariadbbackend

priority=3

persistmaxtime=3600s

persistpoolmax=100

[node2-test]

type=server

address=10.22.23.202

port=3306

protocol=mariadbbackend

priority=2

persistmaxtime=3600s

persistpoolmax=100

[node3-test]

type=server

address=10.22.23.203

port=3306

protocol=mariadbbackend

priority=1

persistmaxtime=3600s

persistpoolmax=100