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TI-2021-08655 Aliases CVE-2021-27085GHSA-vm76-5x29-7jx8

Internet Explorer Remote Code Execution Vulnerability

Priority CRITICAL 95Exploited in the wildPublished · Updated

Key facts

Attack vector
Network
Privileges required
None
User interaction
Required
Attack complexity
Low
Impact type
Code execution
Confidentiality · integrity · availability
Low · High · Low
Fix status
Fixed

Attack profile from CVSS 3.1 · CNA. Fix status from CNA and Microsoft. Impact type from Microsoft.

Summary

Internet Explorer Remote Code Execution Vulnerability

Why it matters now

Exploitation Active In CISA KEV since 2021-11-03CISA due date 2021-11-17
EPSS 0.05448 92nd percentileScored 2026-11-07
Fix Fixed Microsoft: 4 updates

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
Active
Automatable
No
Technical impact
Partial

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

Affected products

VendorProductAffected versionsFixed inStatusSource
MicrosoftInternet Explorer 111.0.0 to before 10.0.17134.208710.0.17134.2087Patch availableCNA
  • Internet Explorer 11 VendorMicrosoft Affected 1.0.0 to before 10.0.17134.2087 Fixed in 10.0.17134.2087 Patch available CNA

CPE configurations NVD · 7

CPEVersionsRoleVendor
cpe:2.3:a:microsoft:internet_explorer:11:-:*:*:*:*:*:*11VulnerableMicrosoft
cpe:2.3:o:microsoft:windows_10_1803:-:*:*:*:*:*:*:*not specified by NVDRunning onMicrosoft
cpe:2.3:o:microsoft:windows_10_1809:-:*:*:*:*:*:*:*not specified by NVDRunning onMicrosoft
cpe:2.3:o:microsoft:windows_10_1909:-:*:*:*:*:*:*:*not specified by NVDRunning onMicrosoft
cpe:2.3:o:microsoft:windows_10_2004:-:*:*:*:*:*:*:*not specified by NVDRunning onMicrosoft
cpe:2.3:o:microsoft:windows_10_20h2:-:*:*:*:*:*:*:*not specified by NVDRunning onMicrosoft
cpe:2.3:o:microsoft:windows_server_2019:-:*:*:*:*:*:*:*not specified by NVDRunning onMicrosoft
  • cpe:2.3:a:microsoft:internet_explorer:11:-:*:*:*:*:*:* Versions 11 Vulnerable ·Microsoft
  • cpe:2.3:o:microsoft:windows_10_1803:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·Microsoft
  • cpe:2.3:o:microsoft:windows_10_1809:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·Microsoft
  • cpe:2.3:o:microsoft:windows_10_1909:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·Microsoft
  • cpe:2.3:o:microsoft:windows_10_2004:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·Microsoft
  • cpe:2.3:o:microsoft:windows_10_20h2:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·Microsoft
  • cpe:2.3:o:microsoft:windows_server_2019:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·Microsoft

Remediation

Microsoft 4 updates

  • KB5000822
    Security Update
    • Internet Explorer 11 10.0.17763.1817
    • Microsoft Edge (EdgeHTML-based) 10.0.17763.1817
    • Windows 10 Version 1809 for 32-bit Systems 10.0.17763.1817
    • Windows 10 Version 1809 for ARM64-based Systems 10.0.17763.1817
    • Windows 10 Version 1809 for x64-based Systems 10.0.17763.1817
    • Windows Server 2019 10.0.17763.1817
    • Windows Server 2019 (Server Core installation) 10.0.17763.1817
  • KB5000809
    Security Update
    • Internet Explorer 11 10.0.17134.2087
    • Microsoft Edge (EdgeHTML-based) 10.0.17134.2087
    • Windows 10 Version 1803 for 32-bit Systems 10.0.17134.2087
    • Windows 10 Version 1803 for ARM64-based Systems 10.0.17134.2087
    • Windows 10 Version 1803 for x64-based Systems 10.0.17134.2087
  • KB5000808
    Security Update
    • Internet Explorer 11 10.0.18363.1440
    • Microsoft Edge (EdgeHTML-based) 10.0.18363.1440
    • Windows 10 Version 1909 for 32-bit Systems 10.0.18363.1440
    • Windows 10 Version 1909 for ARM64-based Systems 10.0.18363.1440
    • Windows 10 Version 1909 for x64-based Systems 10.0.18363.1440
    • Windows Server, version 1909 (Server Core installation) 10.0.18363.1440
Show 1 more Microsoft updates
  • KB5000802
    Security Update
    • Internet Explorer 11 10.0.19043.867
    • Microsoft Edge (EdgeHTML-based) 10.0.19043.867
    • Windows 10 Version 2004 for 32-bit Systems 10.0.19043.867
    • Windows 10 Version 2004 for ARM64-based Systems 10.0.19043.867
    • Windows 10 Version 2004 for x64-based Systems 10.0.19043.867
    • Windows 10 Version 20H2 for 32-bit Systems 10.0.19043.867
    • Windows 10 Version 20H2 for ARM64-based Systems 10.0.19043.867
    • Windows Server, version 2004 (Server Core installation) 10.0.19043.867
    • Windows Server, version 20H2 (Server Core Installation) 10.0.19043.867

Vendor assessments

Microsoft

Microsoft's page for this CVE →

Impact
Remote Code Execution
Exploited
Yes
Publicly disclosed
No
Exploitability
Exploitation Detected

Timeline

  1. 2021-11-03 Added to CISA KEV
  2. 2026-10-02 Threatist record created from CVE-2021-27085
  3. 2026-10-03 Alias added: GHSA-vm76-5x29-7jx8

References

Patch 2

  • TI-2015-00277 Use-after-free vulnerability in Adobe Flash Player before 13.0.0.269 and 14.x through… KEVCVSS 3.1CRITICAL 9.8
  • TI-2015-00275 Unspecified vulnerability in Adobe Flash Player through 13.0.0.262 and 14.x, 15.x, and… KEVCVSS 3.1CRITICAL 9.8
  • TI-2014-01386 Use-after-free vulnerability in Microsoft Internet Explorer 6 through 11 allows remote… KEVCVSS 3.1CRITICAL 9.8
  • TI-2020-01340 Scripting Engine Memory Corruption Vulnerability KEVCVSS 3.1HIGH 8.8
  • TI-2019-00335 Command injection in Microsoft Office KEVCVSS 3.1HIGH 8.8
  • TI-2017-00204 Out-of-bounds write in Microsoft Internet Explorer KEVCVSS 3.1HIGH 8.8
See all 1634 →

Sources

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