An out-of-bounds read was addressed with improved bounds checking. (CVE-2026-84509)
An out-of-bounds read vulnerability in macOS was addressed by improved bounds checking. The issue could cause unexpected system termination when connecting to a malicious SMB server. The vulnerability is fixed in macOS Golden Gate 27, macOS Sequoia 15.8, and macOS Tahoe 26.7.
AI Analysis
Technical Summary
CVE-2026-84509 describes an out-of-bounds read vulnerability in macOS SMB client components. This flaw allows a malicious SMB server to trigger unexpected system termination by exploiting insufficient bounds checking. Apple has fixed this issue in macOS Golden Gate 27, macOS Sequoia 15.8, and macOS Tahoe 26.7 by improving bounds validation to prevent out-of-bounds memory access.
Potential Impact
Connecting to a malicious SMB server may cause the affected macOS system to terminate unexpectedly, potentially resulting in denial of service. There is no indication of code execution or data leakage from the provided information.
Mitigation Recommendations
Apply the official updates to macOS Golden Gate 27, macOS Sequoia 15.8, or macOS Tahoe 26.7 to remediate this vulnerability. These versions include improved bounds checking that fixes the out-of-bounds read issue.
An out-of-bounds read was addressed with improved bounds checking. (CVE-2026-84509)
Description
An out-of-bounds read vulnerability in macOS was addressed by improved bounds checking. The issue could cause unexpected system termination when connecting to a malicious SMB server. The vulnerability is fixed in macOS Golden Gate 27, macOS Sequoia 15.8, and macOS Tahoe 26.7.
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
CVE-2026-84509 describes an out-of-bounds read vulnerability in macOS SMB client components. This flaw allows a malicious SMB server to trigger unexpected system termination by exploiting insufficient bounds checking. Apple has fixed this issue in macOS Golden Gate 27, macOS Sequoia 15.8, and macOS Tahoe 26.7 by improving bounds validation to prevent out-of-bounds memory access.
Potential Impact
Connecting to a malicious SMB server may cause the affected macOS system to terminate unexpectedly, potentially resulting in denial of service. There is no indication of code execution or data leakage from the provided information.
Mitigation Recommendations
Apply the official updates to macOS Golden Gate 27, macOS Sequoia 15.8, or macOS Tahoe 26.7 to remediate this vulnerability. These versions include improved bounds checking that fixes the out-of-bounds read issue.
Technical Details
- Gcve Source
- db.gcve.eu
- Osv Id
- GHSA-fxfm-5vqf-f3wr
- Osv Schema Version
- 1.4.0
- Aliases
- ["CVE-2026-84509"]
- State
- PUBLISHED
Threat ID: 6aa8a1a455bf5e2cf5f3d4e1
Added to database: 09/15/2026, 01:38:44 UTC
Last enriched: 09/15/2026, 01:50:56 UTC
Last updated: 09/15/2026, 03:01:22 UTC
Views: 2
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