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Threats / Microsoft / CVE-2022-21882
CVE-2022-21882 · EUVD no mirror located · GCVE no mirror located Verified 2026-06-22

Microsoft Win32k vulnerability

Microsoft Win32k contains an out-of-bounds write vulnerability enabling privilege escalation. Actively exploited in the wild.

Verdict

Today item — known-exploited.

A memory corruption flaw in Win32k allows attackers to escalate privileges on affected Windows systems. The vulnerability is being actively exploited and carries high exploitation likelihood.

CISA KEV Yes · 2022-02-043EPSS 0.55711 (verify live)4Exploit Public PoC5
01

Is it exploitable?

— the evidence, ranked above the score
Exploit 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
8 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 2022-02-04).
CISA KEV ↗Confirmed
Probability (EPSS)
EPSS 0.55711 — modeled likelihood of exploitation activity.EPSS is a daily-changing model output — open the source for today's value.
Severity / affected
Affected: Microsoft, Win32k. Confirm exact fixed builds in the vendor advisory.
NVD ↗Reported
Weakness (CWE)
Mapped to CWE-787 Out-of-bounds Write — weakness family: Memory safety.CWE assignment from the public NVD record; the weakness class drives how the flaw is exploited.
NVD ↗Reported
WeaknessCWE-787 · Out-of-bounds WriteMemory safety
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
Execute code with restricted privileges on a target Windows system
Business
Attacker gains initial foothold through application or user interaction
2

Keys to the kingdom — privilege/identity takeover narrative 2

Attacker
Trigger the Win32k out-of-bounds write through crafted input or API calls
Business
Memory corruption occurs in kernel-mode graphics subsystem
3

Lateral reach — past segmentation narrative 3

Attacker
Escalate privileges from user-mode to kernel-mode execution context
Business
Attacker obtains SYSTEM-level access to the compromised host
4

Data at risk — exfiltration narrative 4

Attacker
Maintain persistence and execute arbitrary kernel-mode operations
Business
Complete system compromise with ability to disable security controls and deploy malware
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)
  • Public PoC available (VulnCheck)
  • 8 reported-exploitation source(s)
  • CWE weakness mapping (NVD)
  • Public exploit availability
  • 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.