CVE-2026-10648 NULL-pointer dereference in MCUmgr serial/console SMP transport on buffer-pool exhaustion

mcumgrserialprocessfrag in subsys/mgmt/mcumgr/transport/src/serialutil.c calls netbufreset on the result of smppacketalloc before checking it for NULL. smppacketalloc uses netbufallocKNOWAIT against the shared MCUmgr packet pool CONFIGMCUMGRTRANSPORTNETBUFCOUNT, default 4, which returns NULL when...