CVE-2026-86871: An attacker with control of a network file server may be able to cause unexpected system termination in Apple macOS
Description
CVE-2026-86871 is an integer underflow vulnerability in Apple macOS that could allow an attacker controlling a network file server to cause unexpected system termination. The issue has been addressed with improved input validation and fixed in macOS Golden Gate 27, macOS Sequoia 15.8, and macOS Tahoe 26.7.
Affected software
Apple
macOS
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AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
This vulnerability involves an integer underflow in macOS that can be triggered by an attacker with control over a network file server, potentially causing the system to terminate unexpectedly. Apple fixed the issue by improving input validation in the specified macOS versions: Golden Gate 27, Sequoia 15.8, and Tahoe 26.7.
Potential Impact
An attacker who controls a network file server may exploit this vulnerability to cause unexpected system termination on affected macOS versions, leading to denial of service conditions. There is no indication of code execution or data compromise from the provided information.
Mitigation Recommendations
The vulnerability is fixed in macOS Golden Gate 27, macOS Sequoia 15.8, and macOS Tahoe 26.7. Users and administrators should update to these or later versions to remediate the issue.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- apple
- Date Reserved
- 2026-09-08T16:43:41.870Z
- State
- PUBLISHED
Threat ID: 6ad6c19b2cdf04f656e4a8aa
Added to database: 10/20/2026, 01:19:23 UTC
Last enriched: 10/20/2026, 01:49:12 UTC
Last updated: 10/20/2026, 02:08:11 UTC
Views: 4
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