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Threats / Apple / CVE-2021-30657
CVE-2021-30657 · EUVD no mirror located · GCVE no mirror located Verified 2026-06-22

Apple macOS vulnerability

Apple macOS System Preferences contains a logic issue allowing malicious applications to bypass Gatekeeper security checks.

Verdict

Today item — known-exploited.

A logic flaw in macOS System Preferences enables attackers to circumvent Gatekeeper protections, permitting unauthorized code execution. The vulnerability has been exploited in the wild and carries high exploitation likelihood.

CISA KEV Yes · 2021-11-033EPSS 0.68531 (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
3 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 0.68531 — modeled likelihood of exploitation activity.EPSS is a daily-changing model output — open the source for today's value.
Severity / affected
Affected: Apple, macOS. Confirm exact fixed builds in the vendor advisory.
NVD ↗Reported
Weakness (CWE)
Mapped to CWE-862 Missing Authorization — weakness family: Authorization / access control.CWE assignment from the public NVD record; the weakness class drives how the flaw is exploited.
NVD ↗Reported
WeaknessCWE-862 · Missing AuthorizationAuthorization / access control
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 exploits the System Preferences logic flaw to bypass Gatekeeper validation.
Business
Unauthorized code execution on user systems undermines macOS security posture and customer trust in platform protections.
2

Keys to the kingdom — privilege/identity takeover narrative 2

Attacker
I distribute the application through social engineering or compromised channels, relying on Gatekeeper bypass to execute without user warnings.
Business
Widespread infection potential increases incident response costs and liability exposure across the user base.
3

Lateral reach — past segmentation narrative 3

Attacker
I establish persistence and lateral movement within compromised systems to exfiltrate data or deploy secondary payloads.
Business
Data breaches and system compromise lead to regulatory penalties, customer notification obligations, and reputational damage.
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)
  • 3 reported-exploitation source(s)
  • CWE weakness mapping (NVD)
  • Public exploit availability
  • 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.