External risk intelligence

Apple OS Use After Free Vulnerability Leading to System Termination

CVE advisorySeverity: CRITICAL (CVSS 9.8)

CVE-2026-43812

This vulnerability affects local OS components and client-side applications (iOS, iPadOS, macOS, tvOS, visionOS) rather than network-exposed services or internet-facing gateways. The nature of these end-user operating systems and applications typically requires local execution or user interaction, making it very unlikely to be reachable as a public-internet-facing service in common deployments.

Use After Free

Apple Ipados

before 26.615.0 to before 15.7.826.0 to before 26.6

Halo Surface Signal: 1 out of 5 — much less likely to be public-facing.

External exposure likelihood

Horizon Alert

Summary of the vulnerability and why it matters

A use-after-free vulnerability in Apple operating systems could allow an application to cause unexpected system terminations. This critical issue has been addressed in the latest software updates for iOS, iPadOS, macOS, tvOS, and visionOS. The main concern is to confirm relevance and exposure to this type of vulnerability.

Flaw could crash apps or systems.
High severity, critical impact on systems.
Confirm relevance and exposure.

Attack Path

How an attacker could exploit the issue

An attacker could leverage this vulnerability by sending a specially crafted request to an application that interacts with the affected component. This could lead to an unexpected system termination, potentially impacting the availability of the device. The exact journey an attacker would take to reach and trigger this vulnerability is not fully detailed in the provided information.

Entry: Network access required.
Trigger: Specially crafted request to an app.
Risk: Unexpected system termination.

Live Threat

Current exploitation, exposure, and threat context

A use-after-free vulnerability could potentially allow an app to trigger an unexpected system termination when supported by the advisory. This could affect system stability and availability.

System stability.
App execution could cause termination.
Unexpected system shutdowns.

Operational Fix

Recommended remediation, mitigation, and detection steps

This vulnerability impacts Apple's end-user operating systems. The primary teams responsible for addressing this would likely be endpoint management or device administration teams, in coordination with any application owners if specific apps are known to be affected. The immediate first step is to confirm which of these operating systems are deployed, assess their business criticality, and identify the responsible system owner for each.

Endpoint management owns the issue.
Verify affected device and user exposure.
Plan OS updates during maintenance windows.

Supplementary metadata

CVSS vector

Validate whether this threat affects your internet-facing exposure.

Halo Threat Intelligence helps prioritize remediation with Halo Surface Signal and H/A/L/O context. Start exposure validation with a free external attack surface trial.

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Frequently asked questions

What is the software affected by CVE-2026-43812?

This vulnerability affects core components within Apple's ecosystem, including iOS, iPadOS, macOS (Sequoia and Tahoe), tvOS, and visionOS. These operating systems provide the foundational environment for running mobile, desktop, and spatial computing applications. By managing system memory and hardware resources, these platforms ensure that different programs can function simultaneously without interfering with each other's data.

What does a use-after-free weakness mean for CVE-2026-43812?

This CVE involves a 'use-after-free' error, identified as CWE-416. It occurs when a program continues to use a memory location after it has been cleared or released. Because the memory is no longer reserved for that purpose, the program's attempt to access it can cause unstable behavior. In this specific case, that instability manifests as an unexpected system termination.

How is this vulnerability triggered?

The flaw is triggered when an application interacts with the compromised component using a specially crafted request. This action causes the system to improperly handle memory, leading to a crash. Importantly, this issue is not triggered by standard, everyday operations; it requires a specific, malformed input designed to exploit the memory management flaw to force the system to close unexpectedly.

Is my device at risk based on Halo Surface Signal?

Halo Surface Signal indicates that this vulnerability is very unlikely to be reachable as a public-internet-facing service. Because this issue resides in end-user operating systems and client-side applications, it generally requires local execution or user interaction rather than being exposed directly to the open internet. This context helps differentiate it from vulnerabilities that target remote servers or network gateways.

Do I need to take action if I run these Apple operating systems?

Yes. The first step is to identify all devices in your environment running the affected Apple operating systems. Once identified, prioritize these systems for the latest software updates provided by Apple. Coordinate with your device management teams to verify which systems are currently deployed and plan the necessary maintenance to apply the patches that improve memory management and resolve this instability.

References

Written by Nicholas Merritt

Nicholas Merritt is VP of Security Solutions at Halo Security. With more than 25 years across application security, vulnerability prioritization, and offensive security, he helps teams translate threat data into practical exposure validation and remediation focus. He authors Halo Threat Intelligence CVE advisories using Halo Surface Signal and H/A/L/O context to prioritize internet-facing risk.