What macOS Sequoia 15.6.1 Fixes
macOS Sequoia 15.6.1, released August 20, 2025, fixes 1 vulnerability in 1 part of the system, according to Apple's security advisory.
Apple says one of these flaws — CVE-2025-43300 — may already have been exploited. That makes macOS Sequoia 15.6.1 an update to install now rather than at the weekend.
It has since been superseded: the newest security release for macOS Sequoia is macOS Sequoia 15.8.2, from October 26, 2026, which includes these fixes.
| What an attacker could do | Fixes |
|---|---|
| Crash or denial of service | 1 |
Grouped by us from the impact Apple gives for each fix; the impact lines below are Apple's own.
Exploited Before the Fix
Apple flags a fix as possibly exploited when it has a credible report that the flaw was used against real people before the patch. This one is the reason to update today.
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ImageIO Exploited
Processing a malicious image file may result in memory corruption. Apple is aware of a report that this issue may have been exploited in an extremely sophisticated attack against specific targeted individuals.
An out-of-bounds write issue was addressed with improved bounds checking.
CVE-2025-43300
Which Devices Get macOS Sequoia 15.6.1
Apple lists macOS Sequoia 15.6.1 for: macOS Sequoia.
How to Install macOS Sequoia 15.6.1
On the Mac, open System Settings → General → Software Update. Macs that cannot run the newest macOS are offered the update for their own version there.
Security fixes are cumulative: any later release for the same version includes these as well, so if you are already past macOS Sequoia 15.6.1 there is nothing to do.
Every Fix in macOS Sequoia 15.6.1
The rest of Apple's advisory — every fix not already listed above, the most serious kinds first. Each entry is the part of the system affected, Apple's description of the impact and the fix, and the CVE ID.
macOS Sequoia Security Release History
macOS Sequoia 15.6.1 in context: the security releases Apple has published for macOS Sequoia, newest first, with the number of fixes each carried.
| Release | Released | Fixes |
|---|---|---|
| macOS Sequoia 15.7.4 | February 11, 2026 | 51 |
| macOS Sequoia 15.7.3 | December 12, 2025 | 26 |
| macOS Sequoia 15.7.2 | November 3, 2025 | 61 |
| macOS Sequoia 15.7.1 | September 29, 2025 | 1 |
| macOS Sequoia 15.7 | September 15, 2025 | 46 |
| macOS Sequoia 15.6.1 | August 20, 2025 | 1 Exploited |
| macOS Sequoia 15.6 | July 29, 2025 | 92 |
| macOS Sequoia 15.5 | May 12, 2025 | 54 |
| macOS Sequoia 15.4.1 | April 16, 2025 | 2 Exploited |
| macOS Sequoia 15.4 | March 31, 2025 | 165 |
| macOS Sequoia 15.3.2 | March 11, 2025 | 1 Exploited |
The Same Fixes Elsewhere
Apple ships most fixes to every platform that shares the code, and to older versions still under support. These releases close at least one of the same CVEs:
Frequently Asked Questions
What does macOS Sequoia 15.6.1 fix?
1 security vulnerability in 1 part of the system, from Apple's advisory of August 20, 2025.
Was anything fixed in macOS Sequoia 15.6.1 exploited?
Yes. Apple says CVE-2025-43300 may have been exploited before the fix. Install it now.
Which devices can install macOS Sequoia 15.6.1?
macOS Sequoia.
Is macOS Sequoia 15.6.1 the latest security update?
No. macOS Sequoia 15.8.2, from October 26, 2026, is newer and includes these fixes.
Source: About the security content of macOS Sequoia 15.6.1, Apple. Rechecked automatically while Apple is still adding entries.