Threats / Microsoft / CVE-2016-0099
CVE-2016-0099
· EUVD no mirror located
· GCVE no mirror located
Verified 2026-06-22
Microsoft Windows vulnerability
A privilege escalation vulnerability in Windows Secondary Logon Service allows attackers to run arbitrary code with administrator privileges by exploiting improper memory handle management.
Verdict
Today item, not a backlog item.
This vulnerability enables local privilege escalation to administrative level. Active exploitation in the wild and association with ransomware campaigns indicate high-impact real-world abuse. Patching is critical for systems requiring defense against local attackers.
01
Is it exploitable?
— the evidence, ranked above the scoreExploit available
Public proof-of-concept exploit code is cataloged for this vulnerability.We link the existence of the exploit; we do not host or redistribute payloads.
Reported exploitation
6 independent public reports of in-the-wild exploitation are cataloged.Distinct reporting sources (vendor, incident response, government); open them for the underlying claims.
Exploited in the wild
Listed in the CISA Known Exploited Vulnerabilities catalog (added 2022-03-03), flagged for known ransomware use.
Probability (EPSS)
EPSS 0.37164 — modeled likelihood of exploitation activity.EPSS is a daily-changing model output — open the source for today's value.
Severity / affected
Affected: Microsoft, Windows. Confirm exact fixed builds in the vendor advisory.
Weakness (CWE)
Mapped to CWE-264 Permissions/Privileges/Access Control — weakness family: Authorization / access control.CWE assignment from the public NVD record; the weakness class drives how the flaw is exploited.
02
Who’s exploiting it?
— attribution turns risk into urgencyAttribution not established
No confirmed (advisory-backed) threat-actor attribution is established for this record. Absence of a named actor is not absence of compromise — see Coverage & confidence.
03
Why it matters
— the attack path, told twice: adversary, then board1
Front door — unauthenticated access narrative 1
Attacker
I gain initial access to a Windows system through phishing, weak credentials, or another vector, establishing a foothold as a standard user.
Business
An attacker establishes persistence on employee workstations or servers, creating a beachhead for lateral movement and data exfiltration.
2
Keys to the kingdom — privilege/identity takeover narrative 2
Attacker
I craft a malicious request that exploits the Secondary Logon Service's improper handle management to trigger memory corruption.
Business
The organization's access controls are bypassed, allowing the attacker to escalate privileges without additional credentials or detection.
3
Lateral reach — past segmentation narrative 3
Attacker
I execute arbitrary code with administrator privileges, deploying ransomware, backdoors, or credential-stealing malware across the system.
Business
Critical systems are compromised, enabling encryption of sensitive data, deployment of ransomware, or theft of intellectual property and customer information.
04
What to do
— defensible action- Remediate per the vendor advisory — confirm the fixed build for your version and verify exposure.1
Say it to the boardA vulnerability with this evidence profile is a defensible budget line, not a backlog ticket — fund the change against the proof above.
05