CVE-2026-64705: 
macOS vulnerability analysis and mitigation

CVE-2026-64705 is a buffer overflow vulnerability in the HFS component of Apple macOS that allows a local app to cause unexpected system termination or write to kernel memory. It affects macOS Sonoma versions 14.0 through 14.8.6 and macOS Sequoia versions 15.0 through 15.7.6. The vulnerability was disclosed by Apple on May 11, 2026, with additional details added on August 25, 2026. It carries a CVSS v3.1 base score of 5.5 (Medium) (Apple Sequoia Advisory, Apple Sonoma Advisory).

The vulnerability is classified as CWE-120 (Buffer Copy without Checking Size of Input — Classic Buffer Overflow) and resides in the HFS (Hierarchical File System) subsystem of macOS. An attacker with a low-privileged local app can trigger the overflow by supplying oversized input that bypasses bounds checks, potentially overwriting kernel memory. The attack vector is local, requires low privileges, and no user interaction, making it exploitable by any installed application running under a standard user account. Apple addressed the issue with improved bounds checking (Apple Sequoia Advisory, Apple Sonoma Advisory).

Successful exploitation can result in unexpected system termination (denial of service) or unauthorized writes to kernel memory, which could be leveraged for privilege escalation or kernel-level code execution. The vulnerability's kernel memory write primitive poses a risk of system instability and potential escalation of privileges beyond the app's sandbox. Confidentiality impact is assessed as none, while integrity and availability are the primary concerns (Apple Sequoia Advisory, Apple Sonoma Advisory).

As of the available data, there is no evidence of active in-the-wild exploitation, and no public proof-of-concept exploit code has been confirmed. The EPSS score is approximately 0.108%, indicating a low probability of exploitation in the near term. The vulnerability is not listed in the CISA Known Exploited Vulnerabilities catalog, and NVD's SSVC assessment classifies exploitation as "none" and the vulnerability as not automatable (Apple Sequoia Advisory, Apple Sonoma Advisory).

Apple has released patches addressing this vulnerability in macOS Sequoia 15.7.7 and macOS Sonoma 14.8.7, both released on May 11, 2026. Users should update their systems to these versions or later via System Settings > General > Software Update. No configuration-based workarounds have been published; upgrading to the patched release is the recommended and only confirmed remediation (Apple Sequoia Advisory, Apple Sonoma Advisory).

The vulnerability was credited to researchers Surya Kushwaha, Peter Malone, and Dave G. in Apple's official security advisories. No notable independent researcher commentary, media coverage, or significant community discussion beyond standard vulnerability tracking has been identified for this specific CVE (Apple Sequoia Advisory, Apple Sonoma Advisory).