CVE-2026-43748: Apple macOS out-of-bounds write system termination

Executive brief

A vulnerability in macOS could allow a malicious application to cause the computer to crash or shut down unexpectedly. This affects users running older versions of macOS Sequoia and macOS Tahoe. Updating to the latest software versions resolves the issue and maintains system stability.

Technical details

An out-of-bounds write vulnerability exists in macOS Sequoia and macOS Tahoe. The flaw is caused by insufficient bounds checking, which can be triggered by a malicious application. Successful exploitation allows an attacker-controlled app to cause a kernel panic or unexpected system termination, leading to a denial-of-service (DoS) condition. Apple has addressed this issue by implementing improved bounds checking in macOS Sequoia 15.7.8 and macOS Tahoe 26.6.

Affected products

• Apple macOS Sequoia Before 15.7.8
• Apple macOS Tahoe Before 26.6

Timeline

• 2026-07-27: disclosed
• 2026-07-27: patched

References

• https://support.apple.com/en-us/128067
• https://support.apple.com/en-us/128071