SYSTEM privilege escalation via skipped PAC verification
Published Nov 9, 2022 · Updated Aug 10, 2026
Elevation of privilege in HTTP.sys in Microsoft Windows allows local users to gain SYSTEM privileges through crafted Kerberos authentication. HTTP.sys performs authentication in a SYSTEM thread that accepts a modified user-to-user Kerberos ticket without verifying its privilege attribute certificate. A low-privileged domain user can register a localhost HTTP endpoint, submit the altered ticket, and obtain an access token containing injected privileged groups.
Summary
What happened
Elevation of privilege in HTTP.sys in Microsoft Windows allows local users to gain SYSTEM privileges through crafted Kerberos authentication. HTTP.sys performs authentication in a SYSTEM thread that accepts a modified user-to-user Kerberos ticket without verifying its privilege attribute certificate. A low-privileged domain user can register a localhost HTTP endpoint, submit the altered ticket, and obtain an access token containing injected privileged groups.
The record
- CVE
- CVE-2022-41057
- Published
- Nov 9, 2022
- Updated
- Aug 10, 2026
- Vendor
- Microsoft
- Product
- Windows 10 Version 1507
- Classifications
- T1068
- Attack vector
- local
- Privileges
- authenticated
Timeline
How it unfolded
- Nov 9, 2022CVE publishedPublication date reported by the CVE source.
- Aug 10, 2026Record updatedLatest update available in the CVE record.
Exploitability
Present is not the same as exploitable
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Is a vulnerable build present?
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- Affected versionversion=10.0.10240.0 <10.0.10240.19567
What conditions does exploitation require?
What is affected?
Published CVSS scores
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Attacks
What attackers are doing with it
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Weakness, pattern, technique
Public exploit references
- Windows HTTP.SYS Kerberos PAC Verification Bypass proof of conceptproof of concept · demonstrated
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Technologies
Your stack
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Your stack
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