STIGQter: STIG Summary: Microsoft Windows Server 2025 Security Technical Implementation Guide Version: 1 Release: 2 Benchmark Date: 01 Jul 2026:

Windows Server 2025 Windows Update must not obtain updates from other PCs on the internet.

DISA Rule

SV-278104r1181018_rule

Vulnerability Number

V-278104

Group Title

SRG-OS-000480-GPOS-00227

Rule Version

WN25-CC-000260

Severity

CAT III

CCI(s)

CCI-000366 - Implement the security configuration settings.

Weight

Fix Recommendation

Configure the policy value for Computer Configuration >> Administrative Templates >> Windows Components >> Delivery Optimization >> Download Mode to "Enabled" with any option except "Internet" selected.

Acceptable selections include:

Bypass (100)
Group (2)
HTTP only (0)
LAN (1)
Simple (99)

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If the following registry value does not exist or is not configured as specified, this is a finding:

Registry Hive: HKEY_LOCAL_MACHINE
Registry Path: \SOFTWARE\Policies\Microsoft\Windows\DeliveryOptimization\

Value Name: DODownloadMode

Value Type: REG_DWORD
Value: 0x00000000 (0) - No peering (HTTP Only)
0x00000001 (1) - Peers on same NAT only (LAN)
0x00000002 (2) - Local Network / Private group peering (Group)
0x00000063 (99) - Simple download mode, no peering (Simple)
0x00000064 (100) - Bypass mode, Delivery Optimization not used (Bypass)

A value of 0x00000003 (3), internet, is a finding.

Windows Server 2025 Windows Update must not obtain updates from other PCs on the internet.

DISA Rule

Vulnerability Number

Group Title

Rule Version

Severity

CCI(s)

Weight

Fix Recommendation

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Vulnerability Number

Documentable

Rule Version

Severity Override Guidance

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Target Key