In the Linux kernel, the following vulnerability has been resolved: platform/x86: ISST: Validate level in perf mask ioctls… (CVE-2026-89443)
A vulnerability in the Linux kernel's platform/x86 ISST component was resolved by adding validation for user-provided levels in perf mask ioctls. The issue involved lack of bounds checking on the level index used to access performance level data, which could lead to out-of-bounds reads. The fix adds proper bounds checks and rejects disabled SST-PP levels to prevent invalid ioctl input from causing memory access errors.
AI Analysis
Technical Summary
The Linux kernel vulnerability CVE-2026-89443 concerns the ISST platform/x86 code where functions isst_if_get_perf_level_mask() and isst_if_get_base_freq_mask() used user-supplied level values as indices into perf_levels[] without validating them first. This could cause out-of-bounds reads from the per-level offset table when invalid ioctl input was provided. The patch adds bounds checks similar to adjacent level-info helpers and rejects disabled SST-PP levels, preventing invalid memory access.
Potential Impact
This vulnerability could allow an attacker to cause out-of-bounds reads in kernel memory via crafted ioctl calls, potentially leading to information disclosure or kernel instability. However, no known exploits in the wild have been reported.
Mitigation Recommendations
A fix has been applied to the Linux kernel to validate the level parameter in perf mask ioctls and reject invalid inputs. Users should update to the patched kernel version once available to mitigate this issue.
In the Linux kernel, the following vulnerability has been resolved: platform/x86: ISST: Validate level in perf mask ioctls… (CVE-2026-89443)
Description
A vulnerability in the Linux kernel's platform/x86 ISST component was resolved by adding validation for user-provided levels in perf mask ioctls. The issue involved lack of bounds checking on the level index used to access performance level data, which could lead to out-of-bounds reads. The fix adds proper bounds checks and rejects disabled SST-PP levels to prevent invalid ioctl input from causing memory access errors.
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
The Linux kernel vulnerability CVE-2026-89443 concerns the ISST platform/x86 code where functions isst_if_get_perf_level_mask() and isst_if_get_base_freq_mask() used user-supplied level values as indices into perf_levels[] without validating them first. This could cause out-of-bounds reads from the per-level offset table when invalid ioctl input was provided. The patch adds bounds checks similar to adjacent level-info helpers and rejects disabled SST-PP levels, preventing invalid memory access.
Potential Impact
This vulnerability could allow an attacker to cause out-of-bounds reads in kernel memory via crafted ioctl calls, potentially leading to information disclosure or kernel instability. However, no known exploits in the wild have been reported.
Mitigation Recommendations
A fix has been applied to the Linux kernel to validate the level parameter in perf mask ioctls and reject invalid inputs. Users should update to the patched kernel version once available to mitigate this issue.
Technical Details
- Gcve Source
- db.gcve.eu
- Osv Id
- GHSA-5hf2-3p4g-qfhr
- Osv Schema Version
- 1.4.0
- Aliases
- ["CVE-2026-89443"]
Threat ID: 6aa4a02755bf5e2cf5a86b06
Added to database: 09/12/2026, 00:43:19 UTC
Last enriched: 09/12/2026, 01:19:12 UTC
Last updated: 09/12/2026, 01:19:12 UTC
Views: 1
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