Threats / Microsoft / CVE-2016-3309
CVE-2016-3309
· EUVD no mirror located
· GCVE no mirror located
Verified 2026-06-22
Microsoft Windows vulnerability
Windows kernel privilege escalation vulnerability allowing arbitrary code execution in kernel mode. Exploited in the wild and associated with ransomware campaigns.
Verdict
Today item, not a backlog item.
This kernel-mode code execution vulnerability presents critical risk. Active exploitation and ransomware association indicate immediate threat. Organizations must prioritize patching to prevent system compromise and data encryption attacks.
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
4 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 2022-03-15), flagged for known ransomware use.
Probability (EPSS)
EPSS 0.20625 — 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, drive-by download, or network compromise.
Business
Attacker establishes foothold on corporate endpoint, bypassing perimeter controls.
2
Keys to the kingdom — privilege/identity takeover narrative 2
Attacker
I exploit the kernel memory handling flaw to escalate from user-mode to kernel-mode execution.
Business
Attacker obtains system-level privileges, defeating application and OS-level security boundaries.
3
Lateral reach — past segmentation narrative 3
Attacker
I execute arbitrary code with kernel privileges to disable security software and establish persistence.
Business
Endpoint protection is neutralized; attacker gains durable control resistant to removal.
4
Data at risk — exfiltration narrative 4
Attacker
I deploy ransomware payload across the network using kernel-level access to encrypt files and systems.
Business
Critical business data becomes inaccessible; operations halt and ransom demands follow.
5
Lights out — disruption & extortion narrative 5
Attacker
I maintain kernel-mode persistence to prevent recovery and ensure continued extortion leverage.
Business
Organization faces extended downtime, financial loss, reputational damage, and potential regulatory penalties.
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