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Threats / Apple / CVE-2021-30762
CVE-2021-30762 · EUVD no mirror located · GCVE no mirror located Verified 2026-06-22

Apple iOS vulnerability

Apple iOS WebKit use-after-free vulnerability enabling remote code execution through maliciously crafted web content. Affects Safari and other WebKit-dependent applications.

Verdict

Today item — known-exploited.

A memory safety defect in WebKit's HTML parsing allows attackers to achieve arbitrary code execution by delivering malicious web content to vulnerable iOS devices. The vulnerability has been observed in active exploitation.

CISA KEV Yes · 2021-11-033EPSS 0.11074 (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 0.11074 — modeled likelihood of exploitation activity.EPSS is a daily-changing model output — open the source for today's value.
Severity / affected
Affected: Apple, iOS. Confirm exact fixed builds in the vendor advisory.
NVD ↗Reported
Weakness (CWE)
Mapped to 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-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 craft a malicious webpage containing specially formatted HTML that triggers a use-after-free condition in WebKit's parser.
Business
User visits attacker-controlled or compromised website via Safari or WebKit-based browser, leading to device compromise.
2

Keys to the kingdom — privilege/identity takeover narrative 2

Attacker
I host the exploit payload on a website or inject it into legitimate sites through watering hole techniques.
Business
Attackers gain code execution on iOS devices without user interaction beyond visiting a webpage, enabling data theft or device takeover.
3

Lateral reach — past segmentation narrative 3

Attacker
I distribute the malicious content through phishing, social engineering, or ad networks to maximize victim reach.
Business
Large-scale compromise of iOS user base with potential for credential harvesting, surveillance, or lateral movement to corporate networks.
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.