CVE-2026-43809 Denial of service in iOS and iPadOS

What is CVE-2026-43809?

CVE-2026-43809 is a critical denial of service vulnerability in Apple Macos, published on 27 Jul 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.

Official description

An out-of-bounds read was addressed with improved bounds checking. This issue is fixed in iOS 18.7.10 and iPadOS 18.7.10, macOS Sequoia 15.7.8, macOS Sonoma 14.8.8, macOS Tahoe 26.6. An app may be able to cause unexpected system termination.

Weakness: CWE-125

Which versions are affected by CVE-2026-43809?

It affects 1 product.

Products include Apple Macos.

How do I fix CVE-2026-43809?

No fix has been published for CVE-2026-43809 yet. Limit exposure of the affected software until one is available.

Upgrade, then put limits on request size, rate and nesting depth so one client cannot exhaust the service. More about Denial of service.

Is CVE-2026-43809 being exploited?

There is no known exploitation of CVE-2026-43809 in the wild and no public exploit code.

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-g7x9-qq7j-x3gx.