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TI-2021-08257 Aliases CVE-2021-26442GHSA-fjm6-765p-vv8v

Windows HTTP.sys Elevation of Privilege Vulnerability

Priority LOW 37Published · Updated

Key facts

Attack vector
Local
Privileges required
Low
User interaction
None
Attack complexity
Low
Impact type
—
Confidentiality · integrity · availability
High · High · High
Fix status
Fixed

Attack profile from CVSS 3.1 · NVD. Fix status from CNA.

Summary

Windows HTTP.sys Elevation of Privilege Vulnerability

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.0079 56th percentileScored 2026-11-07
Fix Fixed Windows 10 Version 1809 (Microsoft): 10.0.17763.2237Windows Server 2019 (Microsoft): 10.0.17763.2237+25 more products

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
None
Automatable
No
Technical impact
Total

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

VendorProductAffected versionsFixed inStatusSource
MicrosoftWindows 10 Version 180910.0.0 to before 10.0.17763.223710.0.17763.2237Patch availableCNA
MicrosoftWindows Server 201910.0.0 to before 10.0.17763.223710.0.17763.2237Patch availableCNA
MicrosoftWindows Server 2019 (Server Core installation)10.0.0 to before 10.0.17763.223710.0.17763.2237Patch availableCNA
MicrosoftWindows 10 Version 190910.0.0 to before 10.0.18363.185410.0.18363.1854Patch availableCNA
MicrosoftWindows 10 Version 21H110.0.0 to before 10.0.19043.128810.0.19043.1288Patch availableCNA
MicrosoftWindows Server 202210.0.0 to before 10.0.20348.28810.0.20348.288Patch availableCNA
MicrosoftWindows 10 Version 200410.0.0 to before 10.0.19041.128810.0.19041.1288Patch availableCNA
MicrosoftWindows Server version 200410.0.0 to before 10.0.19041.128810.0.19041.1288Patch availableCNA
MicrosoftWindows 10 Version 20H210.0.0 to before 10.0.19042.128810.0.19042.1288Patch availableCNA
MicrosoftWindows Server version 20H210.0.0 to before 10.0.19042.128810.0.19042.1288Patch availableCNA
MicrosoftWindows 11 version 21H210.0.0 to before 10.0.22000.25810.0.22000.258Patch availableCNA
MicrosoftWindows 10 Version 150710.0.0 to before 10.0.10240.1908610.0.10240.19086Patch availableCNA
MicrosoftWindows 10 Version 160710.0.0 to before 10.0.14393.470410.0.14393.4704Patch availableCNA
MicrosoftWindows Server 201610.0.0 to before 10.0.14393.470410.0.14393.4704Patch availableCNA
MicrosoftWindows Server 2016 (Server Core installation)10.0.0 to before 10.0.14393.470410.0.14393.4704Patch availableCNA
MicrosoftWindows 76.1.0 to before 6.1.7601.257406.1.7601.25740Patch availableCNA
MicrosoftWindows 7 Service Pack 16.1.0 to before 6.1.7601.257406.1.7601.25740Patch availableCNA
MicrosoftWindows 8.16.3.0 to before 6.3.9600.201446.3.9600.20144Patch availableCNA
MicrosoftWindows Server 2008 Service Pack 26.0.0 to before 6.0.6003.212516.0.6003.21251Patch availableCNA
MicrosoftWindows Server 2008 Service Pack 2 (Server Core installation)6.0.0 to before 6.0.6003.212516.0.6003.21251Patch availableCNA
MicrosoftWindows Server 2008 Service Pack 26.0.0 to before 6.0.6003.212516.0.6003.21251Patch availableCNA
MicrosoftWindows Server 2008 R2 Service Pack 16.1.0 to before 6.1.7601.257406.1.7601.25740Patch availableCNA
MicrosoftWindows Server 2008 R2 Service Pack 1 (Server Core installation)6.0.0 to before 6.1.7601.257406.1.7601.25740Patch availableCNA
MicrosoftWindows Server 20126.2.0 to before 6.2.9200.234906.2.9200.23490Patch availableCNA
MicrosoftWindows Server 2012 (Server Core installation)6.2.0 to before 6.2.9200.234906.2.9200.23490Patch availableCNA
MicrosoftWindows Server 2012 R26.3.0 to before 6.3.9600.201446.3.9600.20144Patch availableCNA
MicrosoftWindows Server 2012 R2 (Server Core installation)6.3.0 to before 6.3.9600.201446.3.9600.20144Patch availableCNA
  • Windows 10 Version 1809 VendorMicrosoft Affected 10.0.0 to before 10.0.17763.2237 Fixed in 10.0.17763.2237 Patch available CNA
  • Windows Server 2019 VendorMicrosoft Affected 10.0.0 to before 10.0.17763.2237 Fixed in 10.0.17763.2237 Patch available CNA
  • Windows Server 2019 (Server Core installation) VendorMicrosoft Affected 10.0.0 to before 10.0.17763.2237 Fixed in 10.0.17763.2237 Patch available CNA
  • Windows 10 Version 1909 VendorMicrosoft Affected 10.0.0 to before 10.0.18363.1854 Fixed in 10.0.18363.1854 Patch available CNA
  • Windows 10 Version 21H1 VendorMicrosoft Affected 10.0.0 to before 10.0.19043.1288 Fixed in 10.0.19043.1288 Patch available CNA
  • Windows Server 2022 VendorMicrosoft Affected 10.0.0 to before 10.0.20348.288 Fixed in 10.0.20348.288 Patch available CNA
  • Windows 10 Version 2004 VendorMicrosoft Affected 10.0.0 to before 10.0.19041.1288 Fixed in 10.0.19041.1288 Patch available CNA
  • Windows Server version 2004 VendorMicrosoft Affected 10.0.0 to before 10.0.19041.1288 Fixed in 10.0.19041.1288 Patch available CNA
  • Windows 10 Version 20H2 VendorMicrosoft Affected 10.0.0 to before 10.0.19042.1288 Fixed in 10.0.19042.1288 Patch available CNA
  • Windows Server version 20H2 VendorMicrosoft Affected 10.0.0 to before 10.0.19042.1288 Fixed in 10.0.19042.1288 Patch available CNA
  • Windows 11 version 21H2 VendorMicrosoft Affected 10.0.0 to before 10.0.22000.258 Fixed in 10.0.22000.258 Patch available CNA
  • Windows 10 Version 1507 VendorMicrosoft Affected 10.0.0 to before 10.0.10240.19086 Fixed in 10.0.10240.19086 Patch available CNA
  • Windows 10 Version 1607 VendorMicrosoft Affected 10.0.0 to before 10.0.14393.4704 Fixed in 10.0.14393.4704 Patch available CNA
  • Windows Server 2016 VendorMicrosoft Affected 10.0.0 to before 10.0.14393.4704 Fixed in 10.0.14393.4704 Patch available CNA
  • Windows Server 2016 (Server Core installation) VendorMicrosoft Affected 10.0.0 to before 10.0.14393.4704 Fixed in 10.0.14393.4704 Patch available CNA
  • Windows 7 VendorMicrosoft Affected 6.1.0 to before 6.1.7601.25740 Fixed in 6.1.7601.25740 Patch available CNA
  • Windows 7 Service Pack 1 VendorMicrosoft Affected 6.1.0 to before 6.1.7601.25740 Fixed in 6.1.7601.25740 Patch available CNA
  • Windows 8.1 VendorMicrosoft Affected 6.3.0 to before 6.3.9600.20144 Fixed in 6.3.9600.20144 Patch available CNA
  • Windows Server 2008 Service Pack 2 VendorMicrosoft Affected 6.0.0 to before 6.0.6003.21251 Fixed in 6.0.6003.21251 Patch available CNA
  • Windows Server 2008 Service Pack 2 (Server Core installation) VendorMicrosoft Affected 6.0.0 to before 6.0.6003.21251 Fixed in 6.0.6003.21251 Patch available CNA
  • Windows Server 2008 Service Pack 2 VendorMicrosoft Affected 6.0.0 to before 6.0.6003.21251 Fixed in 6.0.6003.21251 Patch available CNA
  • Windows Server 2008 R2 Service Pack 1 VendorMicrosoft Affected 6.1.0 to before 6.1.7601.25740 Fixed in 6.1.7601.25740 Patch available CNA
  • Windows Server 2008 R2 Service Pack 1 (Server Core installation) VendorMicrosoft Affected 6.0.0 to before 6.1.7601.25740 Fixed in 6.1.7601.25740 Patch available CNA
  • Windows Server 2012 VendorMicrosoft Affected 6.2.0 to before 6.2.9200.23490 Fixed in 6.2.9200.23490 Patch available CNA
  • Windows Server 2012 (Server Core installation) VendorMicrosoft Affected 6.2.0 to before 6.2.9200.23490 Fixed in 6.2.9200.23490 Patch available CNA
  • Windows Server 2012 R2 VendorMicrosoft Affected 6.3.0 to before 6.3.9600.20144 Fixed in 6.3.9600.20144 Patch available CNA
  • Windows Server 2012 R2 (Server Core installation) VendorMicrosoft Affected 6.3.0 to before 6.3.9600.20144 Fixed in 6.3.9600.20144 Patch available CNA

CPE configurations NVD · 20

CPEVersionsRoleVendor
cpe:2.3:o:microsoft:windows_10:-:*:*:*:*:*:*:*not specified by NVDVulnerableMicrosoft
cpe:2.3:o:microsoft:windows_10:20h2:*:*:*:*:*:*:*20h2VulnerableMicrosoft
cpe:2.3:o:microsoft:windows_10:21h1:*:*:*:*:*:*:*21h1VulnerableMicrosoft
cpe:2.3:o:microsoft:windows_10:1809:*:*:*:*:*:*:*1809VulnerableMicrosoft
cpe:2.3:o:microsoft:windows_10:1909:*:*:*:*:*:*:*1909VulnerableMicrosoft
cpe:2.3:o:microsoft:windows_10:2004:*:*:*:*:*:*:*2004VulnerableMicrosoft
cpe:2.3:o:microsoft:windows_11:-:*:*:*:*:*:arm64:*not specified by NVDVulnerableMicrosoft
cpe:2.3:o:microsoft:windows_11:-:*:*:*:*:*:x64:*not specified by NVDVulnerableMicrosoft
cpe:2.3:o:microsoft:windows_7:-:sp1:*:*:-:*:-:*not specified by NVDVulnerableMicrosoft
cpe:2.3:o:microsoft:windows_8.1:-:*:*:*:*:*:*:*not specified by NVDVulnerableMicrosoft
  • cpe:2.3:o:microsoft:windows_10:-:*:*:*:*:*:*:* Versions not specified by NVD Vulnerable ·Microsoft
  • cpe:2.3:o:microsoft:windows_10:20h2:*:*:*:*:*:*:* Versions 20h2 Vulnerable ·Microsoft
  • cpe:2.3:o:microsoft:windows_10:21h1:*:*:*:*:*:*:* Versions 21h1 Vulnerable ·Microsoft
  • cpe:2.3:o:microsoft:windows_10:1809:*:*:*:*:*:*:* Versions 1809 Vulnerable ·Microsoft
  • cpe:2.3:o:microsoft:windows_10:1909:*:*:*:*:*:*:* Versions 1909 Vulnerable ·Microsoft
  • cpe:2.3:o:microsoft:windows_10:2004:*:*:*:*:*:*:* Versions 2004 Vulnerable ·Microsoft
  • cpe:2.3:o:microsoft:windows_11:-:*:*:*:*:*:arm64:* Versions not specified by NVD Vulnerable ·Microsoft
  • cpe:2.3:o:microsoft:windows_11:-:*:*:*:*:*:x64:* Versions not specified by NVD Vulnerable ·Microsoft
  • cpe:2.3:o:microsoft:windows_7:-:sp1:*:*:-:*:-:* Versions not specified by NVD Vulnerable ·Microsoft
  • cpe:2.3:o:microsoft:windows_8.1:-:*:*:*:*:*:*:* Versions not specified by NVD Vulnerable ·Microsoft
Show 10 more CPE
CPEVersionsRoleVendor
cpe:2.3:o:microsoft:windows_rt_8.1:-:*:*:*:*:*:*:*not specified by NVDVulnerableMicrosoft
cpe:2.3:o:microsoft:windows_server_2008:-:sp2:*:*:*:*:*:*not specified by NVDVulnerableMicrosoft
cpe:2.3:o:microsoft:windows_server_2008:r2:sp1:*:*:*:*:x64:*r2 sp1VulnerableMicrosoft
cpe:2.3:o:microsoft:windows_server_2012:-:*:*:*:*:*:*:*not specified by NVDVulnerableMicrosoft
cpe:2.3:o:microsoft:windows_server_2012:r2:*:*:*:*:*:*:*r2VulnerableMicrosoft
cpe:2.3:o:microsoft:windows_server_2016:-:*:*:*:*:*:*:*not specified by NVDVulnerableMicrosoft
cpe:2.3:o:microsoft:windows_server_2016:20h2:*:*:*:*:*:*:*20h2VulnerableMicrosoft
cpe:2.3:o:microsoft:windows_server_2016:2004:*:*:*:*:*:*:*2004VulnerableMicrosoft
cpe:2.3:o:microsoft:windows_server_2019:-:*:*:*:*:*:*:*not specified by NVDVulnerableMicrosoft
cpe:2.3:o:microsoft:windows_server_2022:-:*:*:*:*:*:*:*not specified by NVDVulnerableMicrosoft
  • cpe:2.3:o:microsoft:windows_rt_8.1:-:*:*:*:*:*:*:* Versions not specified by NVD Vulnerable ·Microsoft
  • cpe:2.3:o:microsoft:windows_server_2008:-:sp2:*:*:*:*:*:* Versions not specified by NVD Vulnerable ·Microsoft
  • cpe:2.3:o:microsoft:windows_server_2008:r2:sp1:*:*:*:*:x64:* Versions r2 sp1 Vulnerable ·Microsoft
  • cpe:2.3:o:microsoft:windows_server_2012:-:*:*:*:*:*:*:* Versions not specified by NVD Vulnerable ·Microsoft
  • cpe:2.3:o:microsoft:windows_server_2012:r2:*:*:*:*:*:*:* Versions r2 Vulnerable ·Microsoft
  • cpe:2.3:o:microsoft:windows_server_2016:-:*:*:*:*:*:*:* Versions not specified by NVD Vulnerable ·Microsoft
  • cpe:2.3:o:microsoft:windows_server_2016:20h2:*:*:*:*:*:*:* Versions 20h2 Vulnerable ·Microsoft
  • cpe:2.3:o:microsoft:windows_server_2016:2004:*:*:*:*:*:*:* Versions 2004 Vulnerable ·Microsoft
  • cpe:2.3:o:microsoft:windows_server_2019:-:*:*:*:*:*:*:* Versions not specified by NVD Vulnerable ·Microsoft
  • cpe:2.3:o:microsoft:windows_server_2022:-:*:*:*:*:*:*:* Versions not specified by NVD Vulnerable ·Microsoft

Remediation

  • Fix · CNA Windows 10 Version 1809 (Microsoft) Fixed in 10.0.17763.2237
  • Fix · CNA Windows Server 2019 (Microsoft) Fixed in 10.0.17763.2237
  • Fix · CNA Windows Server 2019 (Server Core installation) (Microsoft) Fixed in 10.0.17763.2237
  • Fix · CNA Windows 10 Version 1909 (Microsoft) Fixed in 10.0.18363.1854
  • Fix · CNA Windows 10 Version 21H1 (Microsoft) Fixed in 10.0.19043.1288
  • Fix · CNA Windows Server 2022 (Microsoft) Fixed in 10.0.20348.288
  • Fix · CNA Windows 10 Version 2004 (Microsoft) Fixed in 10.0.19041.1288
  • Fix · CNA Windows Server version 2004 (Microsoft) Fixed in 10.0.19041.1288
  • Fix · CNA Windows 10 Version 20H2 (Microsoft) Fixed in 10.0.19042.1288
  • Fix · CNA Windows Server version 20H2 (Microsoft) Fixed in 10.0.19042.1288
  • Fix · CNA Windows 11 version 21H2 (Microsoft) Fixed in 10.0.22000.258
  • Fix · CNA Windows 10 Version 1507 (Microsoft) Fixed in 10.0.10240.19086
  • Fix · CNA Windows 10 Version 1607 (Microsoft) Fixed in 10.0.14393.4704
  • Fix · CNA Windows Server 2016 (Microsoft) Fixed in 10.0.14393.4704
  • Fix · CNA Windows Server 2016 (Server Core installation) (Microsoft) Fixed in 10.0.14393.4704
  • Fix · CNA Windows 7 (Microsoft) Fixed in 6.1.7601.25740
  • Fix · CNA Windows 7 Service Pack 1 (Microsoft) Fixed in 6.1.7601.25740
  • Fix · CNA Windows 8.1 (Microsoft) Fixed in 6.3.9600.20144
  • Fix · CNA Windows Server 2008 Service Pack 2 (Microsoft) Fixed in 6.0.6003.21251
  • Fix · CNA Windows Server 2008 Service Pack 2 (Server Core installation) (Microsoft) Fixed in 6.0.6003.21251
  • Fix · CNA Windows Server 2008 Service Pack 2 (Microsoft) Fixed in 6.0.6003.21251
  • Fix · CNA Windows Server 2008 R2 Service Pack 1 (Microsoft) Fixed in 6.1.7601.25740
  • Fix · CNA Windows Server 2008 R2 Service Pack 1 (Server Core installation) (Microsoft) Fixed in 6.1.7601.25740
  • Fix · CNA Windows Server 2012 (Microsoft) Fixed in 6.2.9200.23490
  • Fix · CNA Windows Server 2012 (Server Core installation) (Microsoft) Fixed in 6.2.9200.23490
  • Fix · CNA Windows Server 2012 R2 (Microsoft) Fixed in 6.3.9600.20144
  • Fix · CNA Windows Server 2012 R2 (Server Core installation) (Microsoft) Fixed in 6.3.9600.20144

Timeline

  1. 2026-10-02 Threatist record created from CVE-2021-26442
  2. 2026-10-03 Alias added: GHSA-fjm6-765p-vv8v

References

Patch 1

  • TI-2015-02132 Buffer underflow in atmfd.dll in the Windows Adobe Type Manager Library in Microsoft… KEVCVSS 3.1HIGH 8.8
  • TI-2022-10056 Remote Procedure Call Runtime Remote Code Execution Vulnerability CVSS 3.1CRITICAL 9.8
  • TI-2022-06273 HTTP Protocol Stack Remote Code Execution Vulnerability CVSS 3.1CRITICAL 9.8
  • TI-2019-00906 Remote Desktop Services Remote Code Execution Vulnerability CVSS 3.1CRITICAL 9.8
  • TI-2022-15533 Windows Internet Key Exchange (IKE) Protocol Extensions Remote Code Execution Vulnerability CVSS 3.1CRITICAL 9.8
  • TI-2015-01587 Mount Manager in Microsoft Windows Vista SP2, Windows Server 2008 SP2 and R2 SP1, Windows… KEVCVSS 3.1MEDIUM 6.6
See all 2973 →

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences