CVE-2025-27474: Windows Routing and Remote Access Service (RRAS) Information Disclosure Vulnerability

Severity: medium (CVSS 6.5 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 1.8% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2025-04-08 · updated 2026-08-10
Weakness: CWE-908

Description

Use of uninitialized resource in Windows Routing and Remote Access Service (RRAS) allows an unauthorized attacker to disclose information over a network.

Affected products

Microsoft Windows Server 2008: r2-sp1
Microsoft Windows Server 2012: r2
Microsoft Windows Server 2016: before 10.0.14393.7969 — fixed in 10.0.14393.7969
Microsoft Windows Server 2019: before 10.0.17763.7136 — fixed in 10.0.17763.7136
Microsoft Windows Server 2022: before 10.0.20348.3453 — fixed in 10.0.20348.3453
Microsoft Windows Server 2022, 23H2 Edition (Server Core installation): before 10.0.25398.1551 — fixed in 10.0.25398.1551
Microsoft Windows Server 2025: before 10.0.26100.3775 — fixed in 10.0.26100.3775
Microsoft Windows Server 2008 R2 Service Pack 1: from 6.1.7601.0 before 6.1.7601.27670 — fixed in 6.1.7601.27670
Microsoft Windows Server 2008 Service Pack 2: from 6.0.6003.0 before 6.0.6003.23220 — fixed in 6.0.6003.23220
Microsoft Windows Server 2012: from 6.2.9200.0 before 6.2.9200.25423 — fixed in 6.2.9200.25423
Microsoft Windows Server 2012 R2: from 6.3.9600.0 before 6.3.9600.22523 — fixed in 6.3.9600.22523
Microsoft Windows Server 2016: from 10.0.14393.0 before 10.0.14393.7969 — fixed in 10.0.14393.7969
Microsoft Windows Server 2019: from 10.0.17763.0 before 10.0.17763.7136 — fixed in 10.0.17763.7136
Microsoft Windows Server 2022: from 10.0.20348.0 before 10.0.20348.3453 — fixed in 10.0.20348.3453
Microsoft Windows Server 2022, 23H2 Edition (Server Core installation): from 10.0.25398.0 before 10.0.25398.1551 — fixed in 10.0.25398.1551
Microsoft Windows Server 2025: from 10.0.26100.0 before 10.0.26100.3775 — fixed in 10.0.26100.3775

How to fix

Upgrade to a fixed version: Microsoft Windows Server 2016 10.0.14393.7969; Microsoft Windows Server 2019 10.0.17763.7136; Microsoft Windows Server 2022 10.0.20348.3453; Microsoft Windows Server 2022, 23H2 Edition (Server Core installation) 10.0.25398.1551; Microsoft Windows Server 2025 10.0.26100.3775; Microsoft Windows Server 2008 R2 Service Pack 1 6.1.7601.27670; Microsoft Windows Server 2008 Service Pack 2 6.0.6003.23220; Microsoft Windows Server 2012 6.2.9200.25423; Microsoft Windows Server 2012 R2 6.3.9600.22523; Microsoft Windows Server 2016 10.0.14393.7969; Microsoft Windows Server 2019 10.0.17763.7136; Microsoft Windows Server 2022 10.0.20348.3453. Check the vendor advisory for mitigations.

References

https://msrc.microsoft.com/update-guide/vulnerability/CVE-2025-27474

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