The following APAR/PTF needs to be applied to ensure that HostBridge does not become the victim of a storage violation during execution of an HB.js script:
APAR PH35082 (PTF UI75558)
There are also 2 other OPEN APARs dealing with COMMAREA issues in CICS TS 5.6 that you want to keep an eye or get them applied when fixes are available, as they will fix issues that possibly could cause HostBridge to fail:
PH38249: DFHDU0203I REGNNAME A TRANSACTION DUMP WAS TAKEN FOR DUMPCODE: AXG4, TRAN: MB10, TRANUM: 30504, PROGRAM: DFHMIRS.
PH38333: STORAGE VIOLATION CAUSED BY GET_CONTAINER_INTO WHEN COMMAREA > 24K ON DPL REQUEST IS FOLLOWED BY DPL WITHOUT A COMMAREA