CVE-2026-64776 Overview
CVE-2026-64776 is an out-of-bounds read vulnerability [CWE-125] in Apple macOS that allows a local application to disclose kernel memory. Apple addressed the flaw with improved bounds checks across three supported macOS trains. The issue affects macOS Sequoia before 15.7.8, macOS Sonoma before 14.8.8, and macOS Tahoe before 26.6. Exploitation requires local access and user interaction, and the flaw impacts confidentiality without directly affecting integrity or availability. Kernel memory disclosure is a valuable primitive for attackers building multi-stage exploit chains, since leaked pointers and structures can be used to defeat kernel address space layout randomization (KASLR).
Critical Impact
A local application can read kernel memory, exposing sensitive data and enabling bypasses of kernel address randomization that support further exploitation.
Affected Products
- Apple macOS Sequoia prior to 15.7.8
- Apple macOS Sonoma prior to 14.8.8
- Apple macOS Tahoe prior to 26.6
Discovery Timeline
- 2026-07-27 - CVE-2026-64776 published to NVD
- 2026-07-28 - Last updated in NVD database
Technical Details for CVE-2026-64776
Vulnerability Analysis
The flaw is an out-of-bounds read [CWE-125] in a macOS component that fails to validate access boundaries before returning data from a kernel buffer. When a local application invokes the affected code path, the kernel reads beyond the intended buffer limits and returns the residual contents to userspace. The disclosed bytes can include kernel pointers, cryptographic material, or fragments of adjacent kernel objects. Attackers commonly chain such disclosures with a separate memory corruption bug to achieve reliable kernel code execution. Apple resolved the defect by adding improved bounds checks in the affected routine.
Root Cause
The root cause is missing or insufficient boundary validation on a length or index parameter used inside a kernel-mode routine. The routine reads memory based on attacker-influenced input without confirming the request stays within the allocated object. This lets an unprivileged process read data outside the source buffer.
Attack Vector
Exploitation is local and requires user interaction, typically running a malicious or trojanized application on the target host. The attacker does not need elevated privileges. No network path exists, and the vulnerability alone does not grant code execution. It functions as an information disclosure primitive that supports subsequent privilege escalation or sandbox escape.
No public proof-of-concept is available. See the Apple Security Advisory #128067, Apple Security Advisory #128071, and Apple Security Advisory #128072 for vendor technical detail.
Detection Methods for CVE-2026-64776
Indicators of Compromise
- Unsigned or ad-hoc signed binaries executing unusual syscall or IOKit calls associated with kernel interfaces
- macOS endpoints running versions older than 15.7.8, 14.8.8, or 26.6 despite available updates
- Newly installed applications requesting entitlements or driver access shortly before crash reports referencing kernel panics
Detection Strategies
- Monitor process telemetry for unfamiliar processes issuing repeated Mach or IOKit calls that touch the affected subsystem
- Correlate application launches with kernel diagnostic reports under /Library/Logs/DiagnosticReports/ that reference out-of-bounds access
- Alert on execution of unsigned binaries or apps outside of managed software inventories
Monitoring Recommendations
- Track macOS build numbers across the fleet using MDM inventory and flag hosts below the patched versions
- Ingest EndpointSecurity events into a central data lake to baseline normal kernel-interface usage and identify anomalies
- Review Gatekeeper and XProtect telemetry for repeated evaluations of the same suspicious binary
How to Mitigate CVE-2026-64776
Immediate Actions Required
- Update all managed Macs to macOS Sequoia 15.7.8, macOS Sonoma 14.8.8, or macOS Tahoe 26.6
- Enforce update deployment through your MDM by prioritizing this CVE in the next maintenance window
- Restrict installation of untrusted third-party applications and enforce Gatekeeper policies
Patch Information
Apple released fixes in macOS Sequoia 15.7.8, macOS Sonoma 14.8.8, and macOS Tahoe 26.6. Refer to the Apple Security Advisory #128067, Apple Security Advisory #128071, and Apple Security Advisory #128072 for the version-specific release notes.
Workarounds
- No vendor-supplied workaround exists; apply the patch as the primary remediation
- Limit local user execution rights and remove unnecessary local accounts to reduce exposure
- Enforce application allowlisting to block untrusted binaries that could invoke the vulnerable code path
# Verify current macOS version and confirm patched build
sw_vers
# Trigger available software updates via MDM or locally
sudo softwareupdate --install --all --restart
Disclaimer: This content was generated using AI. While we strive for accuracy, please verify critical information with official sources.
