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Threats / Android / CVE-2021-0920
CVE-2021-0920 · EUVD no mirror located · GCVE no mirror located Verified 2026-06-22

Android Kernel vulnerability

Android kernel race condition enables use-after-free leading to privilege escalation. Actively exploited in the wild.

Verdict

Today item — known-exploited.

A race condition in the Android kernel creates a use-after-free vulnerability that allows local attackers to escalate privileges. Active exploitation in the wild indicates immediate risk to deployed Android devices.

CISA KEV Yes · 2022-05-233EPSS 0.00811 (verify live)4
01

Is it exploitable?

— the evidence, ranked above the score
Reported exploitation
4 independent public reports of in-the-wild exploitation are cataloged.Distinct reporting sources (vendor, incident response, government); open them for the underlying claims.
docs.google.com ↗cisa.gov ↗storage.googleapis.com ↗ox.security ↗Confirmed
Exploited in the wild
Listed in the CISA Known Exploited Vulnerabilities catalog (added 2022-05-23).
CISA KEV ↗Confirmed
Probability (EPSS)
EPSS 0.00811 — modeled likelihood of exploitation activity.EPSS is a daily-changing model output — open the source for today's value.
FIRST EPSS ↗High
Severity / affected
Affected: Android, Kernel. Confirm exact fixed builds in the vendor advisory.
NVD ↗Reported
Weakness (CWE)
Mapped to CWE-362 Race Condition, CWE-416 Use After Free — weakness family: Memory safety.CWE assignment from the public NVD record; the weakness class drives how the flaw is exploited.
NVD ↗Reported
WeaknessCWE-362 · Race ConditionCWE-416 · Use After FreeMemory 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
I identify a race condition window in kernel memory management to trigger use-after-free.
Business
Attacker gains kernel-level code execution on the device.
2

Keys to the kingdom — privilege/identity takeover narrative 2

Attacker
I exploit the freed memory reference to execute arbitrary code with elevated privileges.
Business
Device security boundary is compromised; attacker operates with system-level access.
3

Lateral reach — past segmentation narrative 3

Attacker
I persist access and disable security controls or exfiltrate sensitive data.
Business
User data, credentials, and device integrity are at risk across the installed base.
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)
  • 4 reported-exploitation source(s)
  • CWE weakness mapping (NVD)
  • Catalogued by google_android (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 google_androidCNA
    Credited with finding itNo finder named in the public CVE record — the work behind this find is unattributed.