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Threats / Apple / CVE-2023-42916
CVE-2023-42916 · EUVD no mirror located · GCVE no mirror located Verified 2026-06-22

Apple Multiple Products vulnerability

Out-of-bounds read in WebKit affects Apple iOS, iPadOS, macOS, and Safari. Processing malicious web content may disclose sensitive information. Vulnerability is actively exploited in the wild.

Verdict

Today item — known-exploited.

An out-of-bounds read in WebKit's HTML parsing allows attackers to extract sensitive data by crafting malicious web content. The vulnerability affects multiple Apple platforms and third-party products using WebKit. Active exploitation has been confirmed.

CISA KEV Yes · 2023-12-043EPSS 0.17963 (verify live)4
01

Is it exploitable?

— the evidence, ranked above the score
Reported exploitation
6 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 2023-12-04).
CISA KEV ↗Confirmed
Probability (EPSS)
EPSS 0.17963 — modeled likelihood of exploitation activity.EPSS is a daily-changing model output — open the source for today's value.
Severity / affected
Affected: Apple, Multiple Products. Confirm exact fixed builds in the vendor advisory.
NVD ↗Reported
Weakness (CWE)
Mapped to CWE-125 Out-of-bounds Read — weakness family: Memory safety.CWE assignment from the public NVD record; the weakness class drives how the flaw is exploited.
NVD ↗Reported
WeaknessCWE-125 · Out-of-bounds ReadMemory 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
Craft malicious HTML or web content designed to trigger out-of-bounds memory access in WebKit parser
Business
User devices running affected Apple platforms or WebKit-dependent applications become vectors for information disclosure
2

Keys to the kingdom — privilege/identity takeover narrative 2

Attacker
Deliver malicious content via web browsing, email links, or embedded content to trigger the parsing vulnerability
Business
Sensitive data resident in adjacent memory regions is read and exfiltrated, compromising user privacy and confidentiality
3

Lateral reach — past segmentation narrative 3

Attacker
Repeat exploitation across multiple users and devices to harvest disclosed information at scale
Business
Widespread data exposure undermines trust in affected platforms and creates liability for organizations relying on WebKit
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)
  • 6 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.