Known exploited · Microsoft
CVE-2016-0099: Microsoft Windows Secondary Logon Service Privilege Escalation Vulnerability
What it is
A privilege escalation vulnerability exists in Microsoft Windows if the Windows Secondary Logon Service fails to properly manage request handles in memory. An attacker who successfully exploited this vulnerability could run arbitrary code as an administrator.
- Vendor
- Microsoft
- Product
- Windows
- Added to KEV
- March 3, 2022
- CISA due date
- March 24, 2022
- Ransomware use
- Known
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.