In the Linux kernel, the following vulnerability has been resolved: platform/x86: ISST: Validate logical CPU id and clos id Validate max CLOS ID and… (CVE-2026-89438)
A vulnerability in the Linux kernel's platform/x86 ISST component related to validation of logical CPU IDs and CLOS IDs has been resolved. The issue involved improper validation of maximum CLOS ID and logical CPU ID used for core power management features, specifically in calculating MMIO offsets. The fix ensures that any clos level or logical CPU number greater than the supported maximum is rejected.
AI Analysis
Technical Summary
The Linux kernel contained a vulnerability in the platform/x86 ISST (Intel Speed Select Technology) code where the maximum CLOS (Class of Service) ID and logical CPU ID were not properly validated. This could allow invalid clos levels or logical CPU numbers to be used in calculations for MMIO (Memory-Mapped I/O) offsets. The vulnerability has been resolved by adding validation to reject any clos level or logical CPU number exceeding the supported maximum.
Potential Impact
The vulnerability could potentially lead to incorrect MMIO offset calculations due to invalid clos or logical CPU IDs. The exact impact is not detailed in the provided data, and no known exploits in the wild have been reported. Without further details, the impact appears limited to potential kernel-level miscalculations affecting core power management features.
Mitigation Recommendations
A fix has been implemented in the Linux kernel to validate and reject invalid clos levels and logical CPU IDs. Users should apply the official kernel updates containing this fix once available. Patch status is not explicitly confirmed in the provided data; check the vendor advisory for current remediation guidance.
In the Linux kernel, the following vulnerability has been resolved: platform/x86: ISST: Validate logical CPU id and clos id Validate max CLOS ID and… (CVE-2026-89438)
Description
A vulnerability in the Linux kernel's platform/x86 ISST component related to validation of logical CPU IDs and CLOS IDs has been resolved. The issue involved improper validation of maximum CLOS ID and logical CPU ID used for core power management features, specifically in calculating MMIO offsets. The fix ensures that any clos level or logical CPU number greater than the supported maximum is rejected.
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
The Linux kernel contained a vulnerability in the platform/x86 ISST (Intel Speed Select Technology) code where the maximum CLOS (Class of Service) ID and logical CPU ID were not properly validated. This could allow invalid clos levels or logical CPU numbers to be used in calculations for MMIO (Memory-Mapped I/O) offsets. The vulnerability has been resolved by adding validation to reject any clos level or logical CPU number exceeding the supported maximum.
Potential Impact
The vulnerability could potentially lead to incorrect MMIO offset calculations due to invalid clos or logical CPU IDs. The exact impact is not detailed in the provided data, and no known exploits in the wild have been reported. Without further details, the impact appears limited to potential kernel-level miscalculations affecting core power management features.
Mitigation Recommendations
A fix has been implemented in the Linux kernel to validate and reject invalid clos levels and logical CPU IDs. Users should apply the official kernel updates containing this fix once available. Patch status is not explicitly confirmed in the provided data; check the vendor advisory for current remediation guidance.
Technical Details
- Gcve Source
- db.gcve.eu
- Osv Id
- GHSA-vpjv-6qfx-qxxr
- Osv Schema Version
- 1.4.0
- Aliases
- ["CVE-2026-89438"]
Threat ID: 6aa4a02455bf5e2cf5a869b9
Added to database: 09/12/2026, 00:43:16 UTC
Last enriched: 09/12/2026, 01:17:55 UTC
Last updated: 09/12/2026, 01:17:55 UTC
Views: 3
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