macOS: Use After Free
CVE-2026-84545 is a high-severity use after free vulnerability in macOS from Apple, with a CVSS 3.1 base score of 8.8 out of 10. It can be exploited with local access to the system by an attacker with a low-privileged account, without any action from a user. The record lists versions 15.8.2, 26.7.2, 27 as the first without the flaw, so updating macOS to one of those releases or later removes the exposure. There is no confirmed exploitation so far. EPSS estimates a 0.2% chance of exploitation within 30 days, which is low compared with other CVEs.
High severity with no evidence of exploitation so far.
What to do
- Update macOS to 15.8.2 or 26.7.2 or 27, whichever matches your release line, or a later version.
- Read the advisory on support.apple.com for workarounds and exact fixed builds.
Affected products and versions
| Vendor | Product | Affected versions | Fixed in |
|---|---|---|---|
| Apple | macOS | before 15.8.2; before 26.7.2; before 27 | 15.8.2, 26.7.2, 27 |
Version data comes from the organisation that assigned the CVE. Confirm against the vendor advisory before deciding you are unaffected.
How the severity score breaks down
- Attack vector
- LocalThe attacker needs local access or must trick a user into running something.
- Attack complexity
- LowNo special conditions are needed; the attack works reliably.
- Privileges required
- LowA basic user account is enough.
- User interaction
- NoneNo action by a victim is required.
- Scope
- ChangedThe attack can reach beyond the vulnerable component into other systems.
- Confidentiality
- HighAll data handled by the component can be read.
- Integrity
- HighData or code can be modified at will.
- Availability
- HighThe component can be taken down completely.
Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H. Scored by CISA (ADP).
Official description
A use after free issue was addressed with improved memory management. This issue is fixed in macOS Golden Gate 27, macOS Sequoia 15.8.2, macOS Tahoe 26.7.2. An app with App Sandbox restrictions may be able to escape the sandbox and execute code with root privileges.
Source: the CVE record as published by its numbering authority, via NVD and CVE.org.
The underlying weakness: Use After Free
The product reuses or references memory after it has been freed. At some point afterward, the memory may be allocated again and saved in another pointer, while the original pointer references a location somewhere within the new allocation. Any operations using the original pointer are no longer valid because the memory belongs to the code that operates on the new pointer.
How developers prevent this class of flaw
- Choose a language that provides automatic memory management.
- When freeing pointers, be sure to set them to NULL once they are freed. However, the utilization of multiple or complex data structures may lower the usefulness of this strategy.
Timeline
- CVE record published.
- CISA published its SSVC assessment (exploitation: none, automatable: no, technical impact: total).
- Record last changed materially (score, affected products, status or references).
References
Advisories
- support.apple.com/en-us/149035Release Notes
- support.apple.com/en-us/149522Release Notes
- support.apple.com/en-us/149523Release Notes
Other vulnerabilities in macOS
- 8.8 High severity
- 7.5 High severity
- 7.5 High severity
- 7.5 High severity
- 7.5 High severity
- 7.5 High severity
Recent Use After Free vulnerabilities
- 7.7 High severity
- 7.8 High severity
- 7.8 High severity
- 7.1 High severity
- 8.8 High severity
- 7.5 High severity
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