Assessment
Why it matters
CISA lists this vulnerability as known to be exploited; exploitation is confirmed; EPSS is 99.7%; technical severity is CVSS 9.8.
HTTP Protocol Stack Remote Code Execution Vulnerability
Who should care
- Teams operating HTTP Protocol Stack, Windows 10 2004, Windows 10 20h2 +2 more
- Vulnerability and exposure management teams
- Security operations teams monitoring exploitation activity
Response plan
What I would do
- Confirm whether HTTP Protocol Stack, Windows 10 2004, Windows 10 20h2 +2 more is present in the environment.
- Identify affected versions and establish whether vulnerable services are exposed or reachable.
- Apply updates per vendor instructions.
- Review relevant security telemetry for evidence of attempted or successful exploitation.
- Document the remediation decision and track it to verified completion.
Vendor remediation
Patch and remediation links
Use the vendor source below to confirm the correct fixed version, package or mitigation for your affected product.
Technical details
- CVSS vector
- CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
- CWE
- CWE-416
- Affected versions
- Microsoft HTTP Protocol Stack; Microsoft Windows 10 2004 (End Excluding: 10.0.19041.982); Microsoft Windows 10 20h2 (End Excluding: 10.0.19042.982); Microsoft Windows Server 2004 (End Excluding: 10.0.19041.982); Microsoft Windows Server 20h2 (End Excluding: 10.0.19042.982)
- Published
- 11 May 2021
- Attack vector
- Network
- Privileges required
- None
- User interaction
- None
Signal timeline
- CVE published
- Added to CISA KEV
- Latest EPSS score: 99.7%
- Signal calculated at 85