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Threats / Apple / CVE-2021-30900
CVE-2021-30900 · EUVD no mirror located · GCVE no mirror located Verified 2026-06-22

Apple iOS, iPadOS, and macOS vulnerability

Apple GPU drivers in iOS, iPadOS, and macOS contain an out-of-bounds write vulnerability enabling malicious applications to execute code with kernel privileges.

Verdict

Today item — known-exploited.

A local attacker with application execution capability can exploit improper input validation in GPU drivers to write beyond allocated memory boundaries, achieving kernel-level code execution and full system compromise.

CISA KEV Yes · 2023-03-303EPSS 0.05204 (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 2023-03-30).
CISA KEV ↗Confirmed
Probability (EPSS)
EPSS 0.05204 — modeled likelihood of exploitation activity.EPSS is a daily-changing model output — open the source for today's value.
Severity / affected
Affected: Apple, iOS, iPadOS, and macOS. Confirm exact fixed builds in the vendor advisory.
NVD ↗Reported
Weakness (CWE)
Mapped to CWE-20 Improper Input Validation, 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
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 submits specially crafted GPU commands to trigger out-of-bounds memory writes.
Business
User device security is compromised as the application gains kernel-level execution privileges.
2

Keys to the kingdom — privilege/identity takeover narrative 2

Attacker
I leverage the kernel access to disable security mechanisms, install persistent backdoors, or exfiltrate sensitive data.
Business
Confidentiality, integrity, and availability of user data and device are completely compromised.
3

Lateral reach — past segmentation narrative 3

Attacker
I distribute the malicious application through legitimate channels or social engineering to maximize victim reach.
Business
Large user populations across iOS, iPadOS, and macOS platforms face potential compromise.
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)
  • CWE weakness mapping (NVD)
  • Catalogued by apple (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 appleCNA
    Credited with finding itNo finder named in the public CVE record — the work behind this find is unattributed.