Found on master 4725647ea3f84a0478b6489aa5d151f25e8905bf
Single SNMP Agent item
Key: procurve.zabbix.lan
SNMP OID: walk[1.3.6.1.2]

Also tried switched on and off SNMP walk to JSON preprocessing.

Result:

==00:00:16:35.227 1365239== Thread 2:
==00:00:16:35.227 1365239== Use of uninitialised value of size 8
==00:00:16:35.227 1365239== at 0x5BABD20: _itoa_word (_itoa.c:178)
==00:00:16:35.227 1365239== by 0x5BC109B: __vfprintf_internal (vfprintf-internal.c:1516)
==00:00:16:35.227 1365239== by 0x5BABE5F: vfprintf (vfprintf.c:23)
==00:00:16:35.227 1365239== by 0x364583: zbx_log_impl (log.c:390)
==00:00:16:35.227 1365239== by 0x58AC7F: zbx_log_handle (common_log.c:49)
==00:00:16:35.227 1365239== by 0x58D6EB: zbx_activate_item_interface (poller.c:153)
==00:00:16:35.227 1365239== by 0x1ED01B: poller_update_interfaces (async_worker.c:87)
==00:00:16:35.227 1365239== by 0x1ED427: async_worker_entry (async_worker.c:203)
==00:00:16:35.227 1365239== by 0x5BDD5C7: start_thread (pthread_create.c:442)
==00:00:16:35.227 1365239== by 0x5C45D5B: thread_start (clone.S:79)
==00:00:16:35.227 1365239== Uninitialised value was created by a heap allocation
==00:00:16:35.227 1365239== at 0x4865128: malloc (vg_replace_malloc.c:442)
==00:00:16:35.227 1365239== by 0x587D7F: zbx_malloc2 (misc.c:151)
==00:00:16:35.227 1365239== by 0x1E3B87: zbx_async_check_snmp (checks_snmp.c:2704)
==00:00:16:35.227 1365239== by 0x1E87BF: async_initiate_queued_checks (async_poller.c:291)
==00:00:16:35.227 1365239== by 0x1E9293: async_poller_thread (async_poller.c:549)
==00:00:16:35.227 1365239== by 0x445667: zbx_thread_start (threads.c:124)
==00:00:16:35.227 1365239== by 0x1AFDBB: server_startup (server.c:1809)
==00:00:16:35.227 1365239== by 0x1B0DB7: MAIN_ZABBIX_ENTRY (server.c:2220)
==00:00:16:35.227 1365239== by 0x5528E7: zbx_daemon_start (daemon.c:380)
==00:00:16:35.227 1365239== by 0x1AE333: main (server.c:1330)
==00:00:16:35.227 1365239==

==00:00:16:35.203 1365239== Conditional jump or move depends on uninitialised value(s)
==00:00:16:35.203 1365239== at 0x1E7B94: process_async_result (async_poller.c:59)
==00:00:16:35.203 1365239== by 0x1E7F6F: process_snmp_result (async_poller.c:134)
==00:00:16:35.203 1365239== by 0x58B593: async_task_remove (asyncpoller.c:44)
==00:00:16:35.203 1365239== by 0x58B74B: async_event (asyncpoller.c:86)
==00:00:16:35.203 1365239== by 0x592FD03: ??? (in /usr/lib/aarch64-linux-gnu/libevent-2.1.so.7.0.1)
==00:00:16:35.203 1365239== by 0x5931867: event_base_loop (in /usr/lib/aarch64-linux-gnu/libevent-2.1.so.7.0.1)
==00:00:16:35.203 1365239== by 0x1E9263: async_poller_thread (async_poller.c:544)
==00:00:16:35.203 1365239== by 0x445667: zbx_thread_start (threads.c:124)
==00:00:16:35.203 1365239== by 0x1AFDBB: server_startup (server.c:1809)
==00:00:16:35.203 1365239== by 0x1B0DB7: MAIN_ZABBIX_ENTRY (server.c:2220)
==00:00:16:35.203 1365239== by 0x5528E7: zbx_daemon_start (daemon.c:380)
==00:00:16:35.203 1365239== by 0x1AE333: main (server.c:1330)
==00:00:16:35.203 1365239== Uninitialised value was created by a heap allocation
==00:00:16:35.203 1365239== at 0x4865128: malloc (vg_replace_malloc.c:442)
==00:00:16:35.203 1365239== by 0x587D7F: zbx_malloc2 (misc.c:151)
==00:00:16:35.203 1365239== by 0x1E3B87: zbx_async_check_snmp (checks_snmp.c:2704)
==00:00:16:35.203 1365239== by 0x1E87BF: async_initiate_queued_checks (async_poller.c:291)
==00:00:16:35.203 1365239== by 0x1E9293: async_poller_thread (async_poller.c:549)
==00:00:16:35.203 1365239== by 0x445667: zbx_thread_start (threads.c:124)
==00:00:16:35.203 1365239== by 0x1AFDBB: server_startup (server.c:1809)
==00:00:16:35.203 1365239== by 0x1B0DB7: MAIN_ZABBIX_ENTRY (server.c:2220)
==00:00:16:35.203 1365239== by 0x5528E7: zbx_daemon_start (daemon.c:380)
==00:00:16:35.203 1365239== by 0x1AE333: main (server.c:1330)