SYSTEM privilege escalation via heap buffer overflow
Published Jul 12, 2022 · Updated Jul 8, 2025
Out-of-bounds write in Microsoft Windows CSRSS allows local users to execute arbitrary code with SYSTEM privileges via a malicious application. BaseSrvActivationContextCacheDuplicateUnicodeString truncates Length plus two to 16 bits when allocating a heap buffer, then copies the original larger Length. Low-privileged local code execution is required, after which the overwritten CSRSS heap can grant SYSTEM-level code execution.
Summary
What happened
Out-of-bounds write in Microsoft Windows CSRSS allows local users to execute arbitrary code with SYSTEM privileges via a malicious application. BaseSrvActivationContextCacheDuplicateUnicodeString truncates Length plus two to 16 bits when allocating a heap buffer, then copies the original larger Length. Low-privileged local code execution is required, after which the overwritten CSRSS heap can grant SYSTEM-level code execution.
The record
- CVE
- CVE-2022-22049
- Published
- Jul 12, 2022
- Updated
- Jul 8, 2025
- Vendor
- Microsoft
- Product
- Windows 10 Version 1507
- Classifications
- CWE-787, T1068
- Attack vector
- local
- Privileges
- authenticated
Timeline
How it unfolded
- Jul 12, 2022CVE publishedPublication date reported by the CVE source.
- Jul 8, 2025Record updatedLatest update available in the CVE record.
Exploitability
Present is not the same as exploitable
Compare your product and version with the public record. A matching version still requires validation against your environment.
Is a vulnerable build present?
Compare these published version ranges with your installed build and any vendor patches.
- Affected versionversion=10.0.10240.0 <10.0.10240.19360
What conditions does exploitation require?
What is affected?
Published CVSS scores
CVSS describes severity. EPSS estimates exploitation probability.
Attacks
What attackers are doing with it
Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.
Public exploit references
- Microsoft Windows CSRSS Integer Overflow Vulnerability DoSfunctional · validated
- Windows sxssrv BaseSrvActivationContextCacheDuplicateUnicodeString heap buffer overflow proof of conceptproof of concept · demonstrated
Labels summarize the accepted research assessment. They do not indicate a test against your environment.
Technologies
Your stack
See the directory against your own environment.
Your stack
Check the software in your environment
Book a demo to see how Hinoki identifies affected software and validates exploitability in your environment.
Book a demo