A reachable assertion vulnerability exists in the Matter SDK (connectedhomeip) 1.3 thru 1.4, specifically within the Level Control cluster's server tick logic (emberAfLevelControlClusterServerTickCallback). When a MoveToLevel command is executed and followed by a conflicting write to the OperationMode attribute (in the Pump Configuration and Control cluster), an invariant check (minLevel < currentLevel) fails and causes the device to abort. This leads to a denial of service condition. The issue is confirmed in SDK versions 1.3 and 1.4 (commit ab3d5ae), and is triggered remotely without authentication.