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CVE-2023-21674

Microsoft Windows Advanced Local Procedure Call (ALPC) Privilege Escalation

8.8 HIGHActively exploited (CISA KEV)EPSS 41.0%
  1. Published10 Jan 2023
  2. Added to CISA KEV10 Jan 2023
  3. Remediation due31 Jan 2023
Actively exploited (CISA KEV)

Microsoft Windows Advanced Local Procedure Call (ALPC) contains an unspecified vulnerability that allows for privilege escalation.

Added to KEV: 10 Jan 2023Federal remediation due: 31 Jan 2023

Description

Windows Advanced Local Procedure Call (ALPC) Elevation of Privilege Vulnerability

CVSS 3.1 breakdown

Attack vectorLocal
Attack complexityLow
Privileges requiredLow
User interactionNone
ScopeChanged
ConfidentialityHigh
IntegrityHigh
AvailabilityHigh
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H

Affected products

Microsoft Windows 10 1507< 10.0.10240.19685
Microsoft Windows 10 1607< 10.0.14393.5648
Microsoft Windows 10 1809< 10.0.17763.3887
Microsoft Windows 10 20h2< 10.0.19042.2486
Microsoft Windows 10 21h2< 10.0.19044.2486
Microsoft Windows 10 22h2< 10.0.19045.2486
Microsoft Windows 11 21h2< 10.0.22000.1455
Microsoft Windows 11 22h2< 10.0.22621.1105
Microsoft Windows Rt 8.1all versions
Microsoft Windows Server 2012r2
Microsoft Windows Server 2016< 10.0.14393.5648
Microsoft Windows Server 2019< 10.0.17763.3887
Microsoft Windows Server 2022< 10.0.20348.1487

Remediation

Fixed in
Microsoft Windows 10 1507≥ 10.0.10240.19685
Microsoft Windows 10 1607≥ 10.0.14393.5648
Microsoft Windows 10 1809≥ 10.0.17763.3887
Microsoft Windows 10 20h2≥ 10.0.19042.2486
Microsoft Windows 10 21h2≥ 10.0.19044.2486
Microsoft Windows 10 22h2≥ 10.0.19045.2486
Microsoft Windows 11 21h2≥ 10.0.22000.1455
Microsoft Windows 11 22h2≥ 10.0.22621.1105
Microsoft Windows Server 2016≥ 10.0.14393.5648
Microsoft Windows Server 2019≥ 10.0.17763.3887

References

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Frequently asked

Is CVE-2023-21674 being actively exploited?

Yes. CVE-2023-21674 is listed in the CISA Known Exploited Vulnerabilities (KEV) catalog, added 10 Jan 2023.

How severe is CVE-2023-21674?

CVE-2023-21674 has a CVSS 3.1 base score of 8.8, rated high. EPSS estimates a 41.0% probability of exploitation.

Which products are affected by CVE-2023-21674?

Affected products include Microsoft Windows 10 1507, Microsoft Windows 10 1607, Microsoft Windows 10 1809, Microsoft Windows 10 20h2, Microsoft Windows 10 21h2, and 8 more.

How do I fix CVE-2023-21674?

Upgrade affected software to a fixed version, for example Microsoft Windows 10 1507 10.0.10240.19685, Microsoft Windows 10 1607 10.0.14393.5648, Microsoft Windows 10 1809 10.0.17763.3887 or later, then confirm no affected versions remain in your inventory.

How Secuno handles this

Secuno correlates vulnerabilities like CVE-2023-21674 against the real software inventory on every managed device, as each hourly inventory arrives. Rather than a static severity, each match is scored in context: exploit availability, EPSS, the asset's exposure, and business criticality decide where it lands in the queue. Because it is on the CISA KEV list, a risk for it never ranks below high, and the update that fixes it moves to the Emergency patch lane. If an affected version is present anywhere across your portfolio, it surfaces automatically with a prioritised remediation path.

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Data from the NVD, CISA KEV catalog and FIRST EPSS. CVSS 3.1 base score shown where available.