How severe is CVE-2016-3309?

CVE-2016-3309 has a CVSS score of 7.8/10, rated HIGH. Immediate patching is strongly recommended.

Which products are affected by CVE-2016-3309?

CVE-2016-3309 affects the following products: microsoft windows 7, microsoft windows 8.1, microsoft windows 10 1507, microsoft windows 10 1511, microsoft windows 10 1607, microsoft windows rt 8.1, microsoft windows server 2008, microsoft windows server 2012, and 1 more.

How do I patch CVE-2016-3309?

No patch has shipped for CVE-2016-3309 yet — track the microsoft windows 7 advisory for a fixed release and apply the workarounds below in the meantime.

How do I detect CVE-2016-3309 across my infrastructure?

Inventory every microsoft windows 7 deployment and check each version against the affected-products list above.

How do I mitigate CVE-2016-3309 if there is no patch (or I can't update yet)?

If you can't upgrade right away: gate or disable the affected feature, validate untrusted input at the boundary, and avoid passing attacker-controlled data into the vulnerable path. O3's runtime protection blocks exploitation in production as an interim safeguard until the upgrade lands. Alongside that, restrict the management interface to trusted networks and apply the vendor's recommended configuration mitigations.

Is CVE-2016-3309 actively exploited in the wild?

Yes. There are 6 known exploit references for CVE-2016-3309, including 1 documented proof-of-concept exploit on Exploit-DB and 3 in-the-wild exploitations observed on GitHub and other sources. Treat this as actively exploitable and prioritize patching immediately. All exploit code should only be run in an isolated sandbox environment for research or authorized testing — never against production systems without explicit written authorization.

What is the EPSS score for CVE-2016-3309?

CVE-2016-3309 has an EPSS (Exploit Prediction Scoring System) score of 20.5%, placing it in the 98th percentile of all CVEs. EPSS is maintained by FIRST.org and estimates the probability that a vulnerability will be exploited in the wild within the next 30 days. This score warrants monitoring and prompt remediation.

Is CVE-2016-3309 in the CISA Known Exploited Vulnerabilities catalog?

Yes. CVE-2016-3309 (Microsoft Windows Kernel Privilege Escalation Vulnerability) was added to CISA's Known Exploited Vulnerabilities (KEV) catalog on 2022-03-15. CISA required all US federal civilian agencies to remediate this vulnerability by 2022-04-05. The required action was: Apply updates per vendor instructions. This CVE has been used in known ransomware campaigns. Being listed in the KEV catalog is the strongest possible confirmation of active exploitation — treat this as a critical priority.

Which products and versions are affected by CVE-2016-3309?

CVE-2016-3309 affects microsoft windows 7; microsoft windows 8.1; microsoft windows 10 1507; microsoft windows 10 1511, and 5 more product(s). Check the affected-products list on this page against your deployed version to confirm exposure.

When was CVE-2016-3309 published, and has it been updated?

CVE-2016-3309 was published on August 9, 2016 and was last updated on June 17, 2026. Advisory data evolves as severity scores, affected ranges, and exploit intelligence are revised — always check the latest version of the advisory before acting.

🛡️

CISA KEV · ACTIVELY EXPLOITED

HIGH severity

CVE-2016-3309 — Windows 7

HIGH

CVE-2016-3309 is a high-severity (CVSS 7.8) vulnerability in microsoft windows 7. It is in CISA's Known Exploited Vulnerabilities catalog (added 2022-03-15) and has been used in ransomware campaigns — treat it as actively exploited and patch now. No vendor fix is recorded yet; mitigation options are listed below.

The kernel-mode drivers in Microsoft Windows Vista SP2; Windows Server 2008 SP2 and R2 SP1; Windows 7 SP1; Windows 8.1; Windows Server 2012 Gold and R2; Windows RT 8.1; and Windows…

Published

Aug 9, 2016

Updated

Jun 17, 2026

Affected

9 products

Patched

See advisory

Exploits

6 known

Exploitation data as of Oct 23, 2026 · OSV.dev, NVD, CISA KEV, FIRST.org (EPSS)

Exploitation Status

Actively exploited in the wild

Confirmed by CISA's Known Exploited Vulnerabilities catalog on 2022-03-15 — including use in ransomware campaigns. Federal agencies were required to remediate by 2022-04-05.
A successful exploit gives an attacker total control of the affected component, not partial access.

Exploitation and automatability from CISA (KEV catalog and SSVC triage) for CVE-2016-3309.

EPSS Exploitation Probability

via FIRST.org ↗

20.5%probability of exploitation in next 30 days

Moderate Risk0.00%

Lower risk than most CVEs98th percentile — riskier than 98% of all scored CVEsHighest risk

Probability of exploitation in the next 30 days, from FIRST.org EPSS.

How urgent is this, really

CVE-2016-3309 by exploitation likelihood (EPSS) against impact (CVSS). Outside the shaded patch-first corner.

Where this sits among everything scored

Of 395,249 CVEs with a current EPSS score, this one falls in the 10–50% band (highlighted). Counts from FIRST.org, log-scaled.

Description

The kernel-mode drivers in Microsoft Windows Vista SP2; Windows Server 2008 SP2 and R2 SP1; Windows 7 SP1; Windows 8.1; Windows Server 2012 Gold and R2; Windows RT 8.1; and Windows 10 Gold, 1511, and 1607 allow local users to gain privileges via a crafted application, aka "Win32k Elevation of Privilege Vulnerability," a different vulnerability than CVE-2016-3308, CVE-2016-3310, and CVE-2016-3311.

Affected Products

9 products · 11 configurations

windows 7microsoft

all

windows 8.1microsoft

all

windows 10 1507microsoft

all

windows 10 1511microsoft

all

windows 10 1607microsoft

all

windows rt 8.1microsoft

all

Exploits & PoCs

Research use only. For defensive security, authorized penetration testing, and academic research only. Never execute exploit code against systems without explicit written authorization.

EDB-42960localwindows_x86-64

Microsoft Windows 10 RS2 (x64) - 'win32kfull!bFill' Pool Overflow

by siberas · Oct 6, 2017

Exploit-DB Source

Detection & mitigation playbook

Vendor / appliance

Detect
Inventory every microsoft windows 7 deployment and check each version against the affected-products list above.
Remediation status
No patch has shipped for CVE-2016-3309 yet — track the microsoft windows 7 advisory for a fixed release and apply the workarounds below in the meantime.
Mitigate without a patch
If you can't upgrade right away: gate or disable the affected feature, validate untrusted input at the boundary, and avoid passing attacker-controlled data into the vulnerable path. O3's runtime protection blocks exploitation in production as an interim safeguard until the upgrade lands. Alongside that, restrict the management interface to trusted networks and apply the vendor's recommended configuration mitigations.

Frequently Asked Questions

O3 Security · Runtime Protection

Is CVE-2016-3309 being exploited in your environment?

Detect and block the exploit chain at execution, on systems you cannot patch yet.

Protect my workloads How runtime protection works