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Threats / Microsoft / CVE-2019-1214
CVE-2019-1214 · EUVD no mirror located · GCVE no mirror located Verified 2026-06-22

Microsoft Windows vulnerability

Microsoft Windows Common Log File System (CLFS) driver improperly handles objects in memory, enabling privilege escalation attacks.

Verdict

Today item — known-exploited.

A memory handling flaw in the Windows CLFS driver permits local attackers to escalate privileges. Active exploitation in the wild demonstrates practical threat; however, no ransomware campaigns have leveraged this vulnerability.

CISA KEV Yes · 2021-11-033EPSS 0.01324 (verify live)4
01

Is it exploitable?

— the evidence, ranked above the score
Reported exploitation
2 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 2021-11-03).
CISA KEV ↗Confirmed
Probability (EPSS)
EPSS 0.01324 — 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.
NVD ↗Reported
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 gain initial access to a Windows system with limited user privileges.
Business
An attacker establishes a foothold on the endpoint, bypassing perimeter controls.
2

Keys to the kingdom — privilege/identity takeover narrative 2

Attacker
I craft a malicious input that exploits improper object handling in the CLFS driver.
Business
The vulnerability creates an attack surface within a core Windows subsystem.
3

Lateral reach — past segmentation narrative 3

Attacker
I execute code that triggers the memory handling flaw to escalate my privileges to system level.
Business
The attacker gains administrative control, enabling lateral movement and persistence.
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)
  • EPSS probability (FIRST)
  • 2 reported-exploitation source(s)
  • 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.