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Exploited RansomwareCVE from 2016, added in 2022

CVE-2016-0151

Microsoft Windows · Operating systems

Microsoft Windows CSRSS Security Feature Bypass Vulnerability

At a glance

Exploited. Added to CISA’s catalog of exploited vulnerabilities on March 28, 2022.

Used in ransomware attacks, according to CISA.

Affected product: Microsoft Windows (category Operating systems, indicative classification). Name in CISA’s catalog: Microsoft Client-Server Run-time Subsystem (CSRSS).

Microsoft component: Windows kernel (Windows: kernel and drivers).

What should I do?

Apply the security update from Microsoft.

Deadline set by CISA for US federal agencies: 21 days (due April 18, 2022). It only binds those agencies, but it is a useful measure of urgency.

Original text of the required action (CISA)

Apply updates per vendor instructions.

Timeline

  1. Vulnerability published Publication date (NVD)
  2. Exploitation confirmed Added to CISA’s KEV catalog
  3. CISA deadline Remediation deadline set for US federal agencies

The facts, with their sources

Exploitation confirmed
Yes, on March 28, 2022 Date added to the catalog of exploited vulnerabilities. Exploitation itself may have started earlier. Source: KEV catalog, collected September 29, 2026 at 14:57 UTC
Ransomware
Known use Source: KEV catalog, collected September 29, 2026 at 14:57 UTC
Hunt for compromise
Not requested by CISA Source: KEV catalog, collected September 29, 2026 at 14:57 UTC
CISA required action
Apply the security update from Microsoft. Rewritten by this site from CISA’s original text. Source: KEV catalog, collected September 29, 2026 at 14:57 UTC
CISA deadline
April 18, 2022, 21 days Set for US federal agencies: a measure of urgency, not an obligation elsewhere. Source: KEV catalog, collected September 29, 2026 at 14:57 UTC
Microsoft patch
Not available Source: Security Update Guide, collected September 29, 2026 at 14:57 UTC
Vulnerability published
April 12, 2016 Source: National Vulnerability Database (NVD), collected September 29, 2026 at 15:00 UTC
Product according to CISA
Microsoft Client-Server Run-time Subsystem (CSRSS) Filed by this site under “Operating systems” (indicative classification). Source: KEV catalog, collected September 29, 2026 at 14:57 UTC
CVSS vector
CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H Technical detail of the score: attack vector, complexity, impact. Source: National Vulnerability Database (NVD), collected September 29, 2026 at 15:00 UTC

Severity and activity

7.8 / 10 CVSS severity: high

Score from the NVD. Collected Sep 29, 2026.

— Probability of exploitation in the next 30 days (EPSS)

FIRST’s EPSS model. Since exploitation is already confirmed, this figure is mostly useful to compare activity. Collected Sep 29, 2026.

Description

The Client-Server Run-time Subsystem (CSRSS) in Microsoft Windows 8.1, Windows Server 2012 Gold and R2, Windows RT 8.1, and Windows 10 Gold and 1511 mismanages process tokens, which allows local users to gain privileges via a crafted application, aka "Windows CSRSS Security Feature Bypass Vulnerability."

Official description from the NVD, collected Sep 29, 2026. CVE® description © The MITRE Corporation.

The Client-Server Run-time Subsystem (CSRSS) in Microsoft mismanages process tokens, which allows local users to gain privileges via a crafted application.

Summary from CISA (KEV catalog).

CERT-FR advisories

No advisory among the latest CERT-FR publications this site follows. That does not mean there are none.

Information reused under the Open Licence 2.0 (Etalab); the date of last update is shown for each advisory. This site is neither affiliated with nor endorsed by ANSSI.

Sources for this page