Vulnary
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Critical· 9.8official fix available

CVE-2026-43778

A critical flaw in Apple operating systems allows an attacker to free memory and then use it again, potentially crashing the system or corrupting kernel memory. The issue is fixed in recent OS releases. Users should update to the latest version.

publishedJul 27, 2026
last modifiedJul 29, 2026
sourcesNVD
severity · cvss
9.8
critical · how bad it is
exploitation · epss
<1%
37th percentile · chance of exploitation in 30 days
(ai-assisted) A model wrote this summary from the official data, so double-check it against the source before you act on it. Read the official advisory →
auto-deletes from the system
counting…on Aug 27, 2026

An official fix is available, so this entry is kept for 30 days and then removed automatically.

01

Who is affected

Apple devices running iOS 26.5 or earlier, iPadOS 26.5 or earlier, macOS Sequoia 15.7.7 or earlier, macOS Sonoma 14.8.7 or earlier, macOS Tahoe 26.5 or earlier, tvOS 26.5 or earlier, visionOS 26.5 or earlier, watchOS 26.5 or earlier.

02

Real-world impact

An attacker could cause the device to crash or corrupt kernel memory, leading to denial of service or potential privilege escalation.

03

Why this severity

The CVSS score is high because the flaw can be exploited remotely with no authentication or user interaction, and it can compromise confidentiality, integrity, and availability of the entire system.

04

What to do about it

official fix available
recommended steps
  1. 011. Update your device to the latest OS version (iOS 26.6, iPadOS 26.6, macOS Sequoia 15.7.8, macOS Sonoma 14.8.8, macOS Tahoe 26.6, tvOS 26.6, visionOS 26.6, or watchOS 26.6).
  2. 022. Restart the device to complete the update.

NVD-referenced vendor advisory

05

Timeline

  1. Jul 27, 2026 · 3d ago
    Published
    Disclosed and added to the National Vulnerability Database.
  2. Jul 28, 2026 · 2d ago
    Official fix available
    A vendor patch or mitigation now exists — see the remediation steps above.
06

How it’s attacked

Attack vectorNetwork (remote)
Attack complexityLow
Privileges requiredNone
User interactionNone needed
ScopeUnchanged
Confidentiality impactHigh
Integrity impactHigh
Availability impactHigh
07

References & advisories

(ai-assisted) A model wrote this summary from the official data, so double-check it against the source before you act on it. Read the official advisory →