Known exploited · Microsoft
CVE-2009-1123: Microsoft Windows Improper Input Validation Vulnerability
What it is
The kernel in Microsoft Windows does not properly validate changes to unspecified kernel objects, which allows local users to gain privileges via a crafted application.
- Vendor
- Microsoft
- Product
- Windows
- Added to KEV
- March 3, 2022
- CISA due date
- March 24, 2022
- Ransomware use
- Unknown
What CISA requires
Apply updates per vendor instructions.
Forensic triage
No
What to do now
- Find every instance of Windows you run, including the forgotten ones, and check its version against the vendor advisory.
- Apply the vendor's fix or mitigation, before March 24, 2022 if you are bound by CISA's deadline, sooner if it faces the internet.
- Assume it was tried against you already: look for signs of exploitation from the date it was added, not from the day you patched.
References
H2 Security
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Start freeSource: CISA Known Exploited Vulnerabilities Catalog (public domain), catalog version 2026.10.01.