platform/x86: ISST: Validate level in perf mask ioctls (CVE-2026-89443) | HOL Guard CVE

Unknown severity · Source severity not reportedCVE-2026-89443

platform/x86: ISST: Validate level in perf mask ioctls

Answer in brief

CVE-2026-89443 records a Unknown severity vulnerability in platform/x86: ISST: Validate level in perf mask ioctls. The current sources do not mark it as known exploited. The current feed maps Linux/Linux (generic), Linux/Linux (generic). Check affected ranges and fixed versions before updating.

Analysis pending evidence review

HOL Guard separates source facts from reviewed analysis. See the methodology.

Published Sep 11, 2026Updated Sep 11, 2026Source checked Sep 11, 2026First seen by HOL Sep 11, 2026Material review Sep 11, 2026

Upstream Advisory

Key facts

Risk: Unknown severitySource severity not reported
Exploitation: Not marked as known exploited
Affected software: 2 mapped packages or products
Fix availability: Available

Why this deserves its current priority

A CVSS score is not reported in the current record. The current sources do not mark it as known exploited. Treat this as a source-backed prioritization signal, not a statement about your environment.

Analysis status

Analysis pending evidence review

Factual feed record only; HOL analysis is not approved for indexing. Read the methodology.

Affected scope and exposure questions

The current feed maps Linux/Linux (generic), Linux/Linux (generic). Check affected ranges and fixed versions before updating.

Mapped affected packages and fixed versions
Package	Affected range	Fixed version
Linux/Linuxgeneric	>=ea009e4769fa3bd05d4c111c3b6865eb3a9be829 <1a8bab5ceee1a42a78de12d3d69f67516a20588e \|\| >=ea009e4769fa3bd05d4c111c3b6865eb3a9be829 <1889a9156553f0692acd57caf15e877baace1a01 \|\| >=ea009e4769fa3bd05d4c111c3b6865eb3a9be829 <d19385624bdfb577db9c94bb8879992fd5e17bcd \|\| >=ea009e4769fa3bd05d4c111c3b6865eb3a9be829 <80e0d353c86a9a168ad6d213f494796294381538	1a8bab5ceee1a42a78de12d3d69f67516a20588e, 1889a9156553f0692acd57caf15e877baace1a01, d19385624bdfb577db9c94bb8879992fd5e17bcd, 80e0d353c86a9a168ad6d213f494796294381538
Linux/Linuxgeneric	6.4	Not reported

Recommended response

Check inventory. Check lockfiles and deployed manifests for Linux/Linux, Linux/Linux.
Review the reported fix. Update Linux/Linux to 1a8bab5ceee1a42a78de12d3d69f67516a20588e if you use the affected versions. Test the change in a non-production environment first.

Evidence timeline and material changes

Published upstream
Sep 11, 2026
Evidence: source:cvelist:source_dates:source-dates:record
Source modified
Sep 11, 2026
Evidence: source:cvelist:source_dates:source-dates:record
First seen by HOL
Sep 11, 2026

Sources and claim methodology

Upstream source description

In the Linux kernel, the following vulnerability has been resolved: platform/x86: ISST: Validate level in perf mask ioctls isst_if_get_perf_level_mask() and isst_if_get_base_freq_mask() use the user-provided level as an index into perf_levels[] via _read_pp_level_info() and _read_bf_level_info(), but neither helper validates it first. The adjacent level-info helpers reject levels above max_level before reading the same per-level register block. Add the same bounds checks to the mask helpers, and reject disabled SST-PP levels in isst_if_get_perf_level_mask() to match isst_if_get_perf_level_info(). This prevents out-of-bounds reads from the per-level offset table on invalid ioctl input.

Quoted source text, attributed separately from HOL analysis.