CVE-2026-39868: Apple iOS, iPadOS, macOS, tvOS, visionOS and watchOS Improper Input Validation Vulnerability
Apple has fixed an improper input validation flaw (CWE-20) across iOS, iPadOS, macOS, tvOS, visionOS and watchOS. The CNA rates it critical with a CVSS 3.1 score of 9.1, and the description says it can cause unexpected system termination or kernel memory corruption. No confirmed active exploitation appears in the sources consulted.
Overview
Apple has published fixes for an improper input validation flaw (CWE-20) that affects several of its operating systems. According to the record, the issue was addressed with improved input validation, and the fixed builds are listed in the Apple security advisory 127595 and related Apple pages.
Impact
The description states that an app may be able to cause unexpected system termination or corrupt kernel memory. The CVSS 3.1 score recorded by the CNA is 9.1 (critical), with high impact on integrity and availability and no impact on confidentiality. Kernel memory corruption is a serious consequence, but the record does not describe how such an outcome would be reached, and this analysis does not add that detail.
Affected products and versions
- iOS and iPadOS: earlier than 26.5.2, according to the affected list.
- macOS: earlier than 26.5.2, according to the affected list.
- Fixed builds named in the description: iOS and iPadOS 18.7.10, iOS and iPadOS 26.5.2, macOS Sequoia 15.7.8, macOS Sonoma 14.8.8, macOS Tahoe 26.5.2, tvOS 26.6, visionOS 26.6 and watchOS 26.6.
The affected list does not name tvOS, visionOS or watchOS, and the structured fixes field is empty. Administrators should confirm the exact build for each device family in the Apple advisories.
Exploitation status
The record shows that this CVE is not listed in the CISA KEV catalog. No confirmed active exploitation appears in the sources consulted for this analysis. The EPSS model gives a low estimated probability of exploitation (about 0.685%), which is a statistical estimate and not evidence of observed attacks.
Remediation and mitigation
- Update affected Apple devices to the fixed builds named in the Apple advisories, starting with devices that handle sensitive data or are exposed to untrusted apps.
- Use mobile device management or the organisation's update tooling to confirm that each platform reached the required version.
- Restrict the installation of apps to trusted sources, as a general hardening measure. The record does not describe a specific workaround.
Detection guidance
- Review device management reports for devices that still run builds earlier than the fixed versions.
- Monitor for unexpected restarts, crash reports and kernel panic logs on managed devices, as these may reflect the described failure mode. A crash alone does not confirm exploitation.
Limitations of the available information
- The record has no title in the source data, so the title in this analysis was written from the affected product list and the CWE.
- The source status is Undergoing Analysis, so the details may change.
- The structured fixed-version field is empty, and the affected list does not match the fixed builds in the description for every platform.
- The Apple advisory pages were listed as references but their full content was not reviewed here.
- The attack path is not described beyond the statement that an app may trigger the effects, while the CVSS vector is marked as network-accessible. This difference is not explained in the record.
Frequently asked questions
What does CVE-2026-39868 allow?
The description says an app may be able to cause unexpected system termination or corrupt kernel memory. The record does not describe how this would be achieved.
Is this vulnerability being actively exploited?
The CVE is not listed in the CISA KEV catalog in this record, and no confirmed active exploitation appears in the sources consulted. Apply the vendor updates regardless.
This analysis was drafted with AI assistance from verified source data and automatically checked against it.