CVE-2026-84543 Memory corruption in macOS

What is CVE-2026-84543?

CVE-2026-84543 is a high-severity memory corruption vulnerability in Apple Macos, published on 14 Sep 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.

Official description

An out-of-bounds access issue was addressed with improved bounds checking. This issue is fixed in macOS Golden Gate 27, macOS Sequoia 15.8, macOS Tahoe 26.7. Connecting to a malicious SMB server may cause unexpected system termination or corrupt kernel memory.

Weakness: CWE-125

Which versions are affected by CVE-2026-84543?

It affects 1 product.

Products include Apple Macos.

How do I fix CVE-2026-84543?

No fix has been published for CVE-2026-84543 yet. Limit exposure of the affected software until one is available.

Upgrade to the fixed version. Memory-safe languages, compiler hardening and fuzzing prevent most new cases. More about Memory corruption.

Is CVE-2026-84543 being exploited?

There is no known exploitation of CVE-2026-84543 in the wild and no public exploit code.

Public exploit code: 1 proofs of concept on GitHub.

Other vulnerabilities in Apple Macos

• CVE-2026-65400 Apple macOS Improper Authentication Exploited Critical 9.8
• CVE-2024-44146 Security feature bypass in macOS Critical 10.0
• CVE-2024-44148 Security feature bypass in macOS Critical 10.0
• CVE-2023-38586 Security feature bypass in macOS Critical 10.0
• CVE-2023-40455 Security feature bypass in macOS Critical 10.0

All Apple Macos vulnerabilities

Sources

• CVE record
• NVD
• OSV
• GitHub advisory
• How this page is made

Also known as GHSA-2j2x-q52r-gmg8.