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Threats / Microsoft / CVE-2016-0151
CVE-2016-0151 · EUVD no mirror located · GCVE no mirror located Verified 2026-06-22

Microsoft Client-Server Run-time Subsystem (CSRSS) vulnerability

Microsoft CSRSS mismanages process tokens, allowing local users to gain elevated privileges through a crafted application.

Verdict

Today item, not a backlog item.

A local privilege escalation vulnerability in the Client-Server Run-time Subsystem enables attackers with user-level access to execute code with system privileges. Active exploitation and ransomware deployment have been observed.

CISA KEV Yes · 2022-03-283Ransomware use Flagged3EPSS 0.63195 (verify live)4
01

Is it exploitable?

— the evidence, ranked above the score
Reported exploitation
1 independent public report of in-the-wild exploitation are cataloged.Distinct reporting sources (vendor, incident response, government); open them for the underlying claims.
cisa.gov ↗Confirmed
Exploited in the wild
Listed in the CISA Known Exploited Vulnerabilities catalog (added 2022-03-28), flagged for known ransomware use.
CISA KEV ↗Confirmed
Probability (EPSS)
EPSS 0.63195 — modeled likelihood of exploitation activity.EPSS is a daily-changing model output — open the source for today's value.
Severity / affected
Affected: Microsoft, Client-Server Run-time Subsystem (CSRSS). Confirm exact fixed builds in the vendor advisory.
NVD ↗Reported
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.
NVD ↗Reported
WeaknessCWE-264 · Permissions/Privileges/Access ControlAuthorization / access control
02

Who’s exploiting it?

— attribution turns risk into urgency
Attribution 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 board
1

Front door — unauthenticated access narrative 1

Attacker
I craft a malicious application that exploits token mismanagement in CSRSS to request elevated privileges.
Business
An attacker gains local code execution with system-level permissions on affected endpoints.
2

Keys to the kingdom — privilege/identity takeover narrative 2

Attacker
I execute my application on a compromised system where I already have user-level access.
Business
The vulnerability is triggered, bypassing Windows privilege boundaries and granting administrative control.
3

Lateral reach — past segmentation narrative 3

Attacker
I deploy ransomware or additional malicious payloads using the elevated privileges I have obtained.
Business
Critical systems become compromised, leading to data encryption, operational disruption, and potential financial extortion.
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

Coverage & confidence

— what we know, and what we don’t

Established (cited)

  • KEV listing (CISA)
  • Ransomware-use flag (CISA)
  • EPSS probability (FIRST)
  • 1 reported-exploitation source(s)
  • CWE weakness mapping (NVD)
  • Catalogued by microsoft (CNA)
  • Coverage gaps — stated, not hidden

  • No EUVD / GCVE mirror in feed — single-authority dependency for the identifier.
  • EPSS & exposure are time-varying; verify live at the source.
  • Threat-actor attribution not established from feed data — absence of a name is not absence of compromise.
  • No finder/reporter credit recorded in the public CVE entry — the work behind this find is unattributed.
  • Disclosure & credit2
    Catalogued by microsoftCNA
    Credited with finding itNo finder named in the public CVE record — the work behind this find is unattributed.