External risk intelligence

Apple OS Shortcut Race Condition Allows Sandbox Escape

CVE advisorySeverity: CRITICAL (CVSS 9.0)

CVE-2026-20677

The vulnerability affects client-side operating systems (iOS, iPadOS, macOS, visionOS) and involves a sandbox bypass issue within Shortcuts, which is a local application-level feature. It is not an internet-facing service or network-accessible gateway.

Apple Ipados

before 18.7.526.0 to before 26.3before 14.8.4before 26.3

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

This advisory details a critical vulnerability affecting Apple operating systems, specifically related to how symbolic links are handled, which could allow shortcuts to bypass security restrictions. While the direct business impact is not immediately clear, such vulnerabilities can potentially lead to broader security concerns if exploited.

A technical flaw could bypass security.
Understand potential risks to our systems.
Confirm relevance and investigate exposure.

Attack Path

How an attacker could exploit the issue

An attacker could potentially exploit a race condition related to symbolic link handling to bypass sandbox restrictions. This could allow a malicious shortcut to gain unauthorized access to sensitive data or perform actions beyond its intended permissions.

No authentication needed.
Shortcut triggers sandbox bypass.
Data exposure and unauthorized actions.

Live Threat

Current exploitation, exposure, and threat context

A race condition in handling symbolic links could allow a shortcut to bypass sandbox restrictions on affected Apple operating systems. This could potentially impact the integrity and confidentiality of data within the system.

System data and user files at risk.
Shortcut execution could bypass sandbox.
Unauthorized access to sensitive information.

Operational Fix

Recommended remediation, mitigation, and detection steps

Given this vulnerability impacts Apple operating systems and could allow a shortcut to bypass sandbox restrictions, responsibility likely falls to device owners and platform administrators. The first practical move is to inventory all affected Apple devices, confirm their exposure and criticality, and then coordinate updates based on risk.

Identify and own affected Apple devices.
Verify shortcut usage and sandbox exposure.
Plan and execute OS updates accordingly.

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-2026-20677?

This vulnerability affects core Apple operating systems, including iOS, iPadOS, macOS, and visionOS. These platforms power a wide range of devices—from iPhones and iPads to Mac computers and spatial computing headsets. The issue resides within the Shortcuts feature, a built-in automation tool that allows users to create sequences of actions across apps. Because these systems manage deep integration between user data and hardware, security boundaries like sandboxes are essential for protecting files.

What is a race condition in the context of this vulnerability?

A race condition, specifically CWE-362 and CWE-367, occurs when a system performs operations in an unintended sequence. In this case, the flaw involves how the system processes symbolic links—shortcuts to other files. If an attacker can time a malicious action to occur precisely while the system is handling these links, they can confuse the operating system. This window of opportunity allows a shortcut to break out of its sandbox, effectively ignoring the security rules meant to restrict it.

How does a shortcut trigger this sandbox bypass?

The bypass occurs when the operating system's file handling logic is subverted during a race condition. It is important to note that this is not triggered by simple, benign shortcut use; it requires the execution of a crafted shortcut designed to exploit the timing of file access. If a shortcut does not involve manipulating symbolic links or attempting to access files outside its permitted boundary, the specific preconditions required for this vulnerability are not met.

Is my device at risk based on Halo Surface Signal?

Halo Surface Signal indicates that the risk of remote, automated exploitation is very low. Because this issue affects local, client-side operating systems rather than internet-facing services or network gateways, it is not something an attacker can typically trigger over the network. The primary risk involves local execution, meaning the potential for widespread, drive-by attacks is significantly reduced compared to flaws found in web servers or remote infrastructure.

What should I do if I manage these Apple devices?

The most effective step is to prioritize updating all managed devices to the latest patched versions provided by Apple, such as iOS 18.7.5 or macOS Sequoia 15.7.4. Start by creating an inventory of your fleet to identify which units are still running older, vulnerable OS builds. Once identified, schedule these updates to ensure devices receive the improved symbolic link handling that closes the bypass window, neutralizing the threat posed by malicious shortcuts.

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.