External risk intelligence

Apple Operating Systems Input Validation Vulnerability.

CVE advisorySeverity: CRITICAL (CVSS 9.8)

CVE-2025-43347

The vulnerability affects client operating systems (iOS, iPadOS, macOS, tvOS, visionOS, watchOS). These are end-user devices rather than internet-facing infrastructure services, web applications, or edge gateways. While they connect to the internet, they are not typically deployed as publicly accessible services where the vulnerable surface is exposed for general inbound connection.

Apple Ipados

before 26.0

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

An input validation flaw has been identified in Apple's operating systems, including iOS, iPadOS, macOS, tvOS, visionOS, and watchOS. This vulnerability could allow for significant compromise of affected devices.

Vulnerable code was removed from Apple operating systems.
It affects a wide range of consumer devices.
Confirm relevance and exposure for affected device families.

Attack Path

How an attacker could exploit the issue

An attacker could reach this vulnerability remotely without needing any special privileges. The issue stems from improper input validation, which, when triggered, could lead to severe consequences.

No special access required.
Vulnerable input validation.
High impact: data, availability, integrity.

Live Threat

Current exploitation, exposure, and threat context

An input validation issue in Apple devices could allow an attacker to affect system behavior or sensitive information when supported by the advisory. This vulnerability exists in operating systems like iOS, iPadOS, macOS, tvOS, visionOS, and watchOS.

Device system data could be affected.
Exposure may happen through malformed input.
Realistic consequence could include system instability.

Operational Fix

Recommended remediation, mitigation, and detection steps

The real-world impact of this vulnerability likely falls under the purview of device owners and potentially IT administrators managing Apple device fleets. The first practical step is to identify all affected Apple devices, determine their business criticality, and confirm their network exposure. Owners should then coordinate remediation efforts, prioritizing devices with higher exposure or business impact.

Device owners should manage the issue.
Verify device inventory and exposure.
Plan and coordinate updates.

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-2025-43347?

This CVE affects the core operating systems for Apple's ecosystem, including iOS, iPadOS, macOS, tvOS, visionOS, and watchOS. These platforms power billions of personal and professional devices, handling everything from daily communications and application management to system-level security and data storage.

What does an input validation vulnerability mean for CVE-2025-43347?

This flaw belongs to the Improper Input Validation class (CWE-20). In plain terms, it means the operating system fails to properly check or sanitize incoming data. Because the system trusts this malformed input, it may process it incorrectly, potentially leading to unauthorized system behavior, data compromise, or instability.

How is this vulnerability triggered?

The issue is triggered when the operating system receives and processes specifically crafted, malformed input. Importantly, the flaw does not require the attacker to have special user privileges or prior access to the device to initiate the request. The vulnerability is effectively bypassed once the underlying code responsible for the flawed validation is removed by the system update.

Why should I care about CVE-2025-43347 if I use Apple devices?

While these operating systems are central to daily tasks, Halo Surface Signal notes that this vulnerability affects client devices rather than typical internet-facing server infrastructure. Because these are end-user devices, they are not usually deployed as public services. However, because the vulnerability allows remote, unauthenticated interaction, you should remain aware of your devices' software versions.

What should I do to address this Apple vulnerability?

Your first step is to verify the current software version of your Apple devices. Check your system settings to ensure you are running the latest version of your respective operating system (such as iOS 26, macOS Tahoe 26, etc.). Because this fix involves the removal of vulnerable code, keeping your devices updated to the latest software release is the primary method to mitigate the risk.

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.