AppleCVE-2026-84539

Apple macOS: out-of-bounds write

CVE-2026-84539 · Published Oct 26, 2026 · updated Oct 27, 2026

Unrated

Fix: upgrade to 26.7.2 or later (2 fixed versions below)

An out-of-bounds write issue was addressed with improved bounds checking. This issue is fixed in macOS Golden Gate 27, macOS Tahoe 26.7.2. An app may be able to cause unexpected system termination.

Affected versions

Package	Affected	Fixed in
macOS Product	< 26.7.2	26.7.2
	< 27	27

Details and references

Severity from: no source yet

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