Sandboxes untrusted applications to prevent them from modifying critical OS files.

Placing Build 558 alongside contemporary solutions (e.g., CrowdStrike Falcon, Microsoft Defender for Endpoint, Trend Micro Apex One) reveals a mixed picture: SEP 14.3 remains strong in policy-driven control and on-network detection but lags in cloud-native features like real-time threat hunting dashboards out of the box. However, Build 558 excels in air-gapped and legacy OS environments (Windows 7, Server 2008 R2) where competitors require modern kernels or persistent internet connectivity.

: Build 558 significantly overhauled the local signature framework. By offloading complex analysis to Broadcom's cloud analytics engine , the local agent requires significantly less disk space for virus definitions, reducing network bandwidth usage during LiveUpdate cycles.

Several specific improvements distinguish Build 558 from its predecessors (e.g., Build 526 or 556):

: Windows 10 (up to version 2004 / 20H1), Windows 8.1, and Windows 7 SP1 (with SHA-2 signing support).

A new policy setting allowed granular control over USB devices based on serial numbers and device classes, improving defenses against air-gap jumps via infected removable media.

Generate customized 32-bit or 64-bit client MSI installation packages within the updated SEPM.

| Release Name | Version (Build Number) | Release Date | End of Service | |---|---|---|---| | 14.4 | 14.4.115.0000 | March 2026 | - | | 14.3 RU10 Patch 1 | 14.3.12167.10000 | November 2025 | - | | 14.3 RU9 Patch 2 | 14.3.11237.9000 | November 2025 | - | | 14.3 RU8 Patch 3 | 14.3.10178.8000 | November 2025 | - | | 14.3 RU10 | 14.3.12154.10000 | February 2025 | - | | 14.3 RU9 | 14.3.11216.9000 | June 2024 | - | | | 14.3.558.0000/.1000 | Early 2019 | N/A | | 14.3 RU1 MP1 | 14.3.1169.0010 | - | - | | 14.3 RU2 | 14.3.5200.XXXX | - | - |

At its heart, SEP 14.3 Build 558 is composed of several tightly integrated protection layers:

Check if there are available for the 14.3 branch. Help with troubleshooting an upgrade from version 14.2. Client only patch Endpoint Protection 14.3 (14.3.558.0000)

Build 558 consolidates critical security components to ensure comprehensive threat prevention, detection, and response. 1. Multi-Layered Threat Protection

To ensure maximum security with SEP 14.3, follow these best practices:

Before diving into specifics, it helps to view the full versioning context: