Threats / Apple / CVE-2021-30900
CVE-2021-30900
· EUVD no mirror located
· GCVE no mirror located
Verified 2026-08-04
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 · 2023-03-304EPSS 0.05204 (verify live)5CVSS 7.8 (CISA)3CISA SSVC Exploitation: active · Automatable: no · Impact: total3
01
Is it exploitable?
— the evidence, ranked above the scoreReported 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).
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
CVSS 7.8 (CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H) · Affected: Apple, iOS, iPadOS, and macOS. Confirm exact fixed builds in the vendor advisory.CVSS — CISA-assigned via the ADP container (CVE.org), version 3.1; the CNA left no metrics, so CISA's own score is used ahead of NVD.
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 (may be stale); the weakness class drives how the flaw is exploited.
CISA SSVC (triage disposition)
Exploitation: active · Automatable: no · Technical Impact: totalCISA's own stakeholder-specific triage inputs, published in the CVE record (CISA Coordinator role). NOTE: this is CISA's three decision points; the final Act/Attend/Track decision also requires a Mission & Well-being input not published here, so no overall decision is asserted.
Currency of the record
CISA added this to its KEV catalog 583 days after the CVE record was published.KEV lag = CISA-KEV dateAdded − CVE.org datePublished; a floor on how long the known-exploited flaw sat in the public record before the federal catalog listed it. Severity/weakness here is CNA- or CISA-assigned (current at disclosure), independent of NVD's analysis backlog.
02
Who’s exploiting it?
— attribution turns risk into urgencyAttribution 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 board1
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