CVE-2026-89443 (GCVE-0-2026-89443)
Vulnerability from cvelistv5
Published
2026-09-11 19:43
Modified
2026-10-19 08:46
Severity ?
7.1 (High) - CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:H
Summary
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.
References
Impacted products
Vendor Product Version
Linux Linux Version: ea009e4769fa3bd05d4c111c3b6865eb3a9be829
Version: ea009e4769fa3bd05d4c111c3b6865eb3a9be829
Version: ea009e4769fa3bd05d4c111c3b6865eb3a9be829
Version: ea009e4769fa3bd05d4c111c3b6865eb3a9be829
Version: ea009e4769fa3bd05d4c111c3b6865eb3a9be829
 Create a notification for this product.
Show details on NVD website

To clipboard 

{
  "containers": {
    "cna": {
      "affected": [
        {
          "defaultStatus": "unaffected",
          "product": "Linux",
          "programFiles": [
            "drivers/platform/x86/intel/speed_select_if/isst_tpmi_core.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "lessThan": "beb22ebf76c0415f22d2d0c3f1ff0627e7ae4a68",
              "status": "affected",
              "version": "ea009e4769fa3bd05d4c111c3b6865eb3a9be829",
              "versionType": "git"
            },
            {
              "lessThan": "1a8bab5ceee1a42a78de12d3d69f67516a20588e",
              "status": "affected",
              "version": "ea009e4769fa3bd05d4c111c3b6865eb3a9be829",
              "versionType": "git"
            },
            {
              "lessThan": "1889a9156553f0692acd57caf15e877baace1a01",
              "status": "affected",
              "version": "ea009e4769fa3bd05d4c111c3b6865eb3a9be829",
              "versionType": "git"
            },
            {
              "lessThan": "d19385624bdfb577db9c94bb8879992fd5e17bcd",
              "status": "affected",
              "version": "ea009e4769fa3bd05d4c111c3b6865eb3a9be829",
              "versionType": "git"
            },
            {
              "lessThan": "80e0d353c86a9a168ad6d213f494796294381538",
              "status": "affected",
              "version": "ea009e4769fa3bd05d4c111c3b6865eb3a9be829",
              "versionType": "git"
            }
          ]
        },
        {
          "defaultStatus": "affected",
          "product": "Linux",
          "programFiles": [
            "drivers/platform/x86/intel/speed_select_if/isst_tpmi_core.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "status": "affected",
              "version": "6.4"
            },
            {
              "lessThan": "6.4",
              "status": "unaffected",
              "version": "0",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.6.*",
              "status": "unaffected",
              "version": "6.6.157",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.12.*",
              "status": "unaffected",
              "version": "6.12.109",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.18.*",
              "status": "unaffected",
              "version": "6.18.50",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "7.2.*",
              "status": "unaffected",
              "version": "7.2.4",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "*",
              "status": "unaffected",
              "version": "7.3",
              "versionType": "original_commit_for_fix"
            }
          ]
        }
      ],
      "cpeApplicability": [
        {
          "nodes": [
            {
              "cpeMatch": [
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "6.6.157",
                  "versionStartIncluding": "6.4",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "6.12.109",
                  "versionStartIncluding": "6.4",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "6.18.50",
                  "versionStartIncluding": "6.4",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "7.2.4",
                  "versionStartIncluding": "6.4",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "7.3",
                  "versionStartIncluding": "6.4",
                  "vulnerable": true
                }
              ],
              "negate": false,
              "operator": "OR"
            }
          ]
        }
      ],
      "descriptions": [
        {
          "lang": "en",
          "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nplatform/x86: ISST: Validate level in perf mask ioctls\n\nisst_if_get_perf_level_mask() and isst_if_get_base_freq_mask() use the\nuser-provided level as an index into perf_levels[] via\n_read_pp_level_info() and _read_bf_level_info(), but neither helper\nvalidates it first.\n\nThe adjacent level-info helpers reject levels above max_level before\nreading the same per-level register block. Add the same bounds checks to\nthe mask helpers, and reject disabled SST-PP levels in\nisst_if_get_perf_level_mask() to match isst_if_get_perf_level_info().\n\nThis prevents out-of-bounds reads from the per-level offset table on\ninvalid ioctl input."
        }
      ],
      "metrics": [
        {
          "cvssV3_1": {
            "baseScore": 7.1,
            "baseSeverity": "HIGH",
            "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:H",
            "version": "3.1"
          },
          "scenarios": [
            {
              "lang": "en",
              "value": "AV:L - The bug is reached only via local ioctl(ISST_IF_GET_PERF_LEVEL_CPU_MASK or ISST_IF_GET_BASE_FREQ_CPU_MASK) on /dev/isst_interface, dispatched through isst_if_def_ioctl() to the TPMI SST helpers; there is no network, Bluetooth, or physical-device path into these functions.\nAC:L - The attacker fully controls the ioctl argument, including the 8-bit level used as perf_levels[level] with no pre-fix bounds check; the out-of-bounds table read and following MMIO readq() occur deterministically, with no race or attacker-uncontrollable memory layout required.\nPR:L - isst_if_open() and both GET mask ioctls perform no capable() check; CAP_SYS_ADMIN is required only for SST write/set commands, so a local process that can open /dev/isst_interface can reach this read path without init-namespace admin capabilities.\nUI:N - The attacker opens /dev/isst_interface and issues the crafted ioctl from their own process; no separate victim action such as mounting a filesystem or opening a file is required.\nS:U - The out-of-bounds kernel/MMIO read and any resulting oops stay within the host kernel security authority; this is not a VM escape, IOMMU bypass, or other cross-boundary impact.\nC:H - User-supplied level (0-255) indexes perf_levels[] (at most 8 entries), reading adjacent heap as a signed mmio_offset that is then used in readq(); the 64-bit result is copied to userspace when punit_cpu_map is set, an out-of-bounds read rated High unless strictly a few bytes.\nI:N - Both helpers only issue MMIO readq() and copy_to_user of the resulting mask; there is no writeq, heap write, type confusion, or control-flow hijack primitive on this path.\nA:H - sst_base is a bounded ioremap from devm_ioremap_resource(); a heap-derived mmio_offset can drive readq() outside that mapping and oops, and the perf_levels[] over-read itself can fault on hardened kernels; any kernel crash is High availability impact."
            }
          ]
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-10-19T08:46:52.766Z",
        "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "shortName": "Linux"
      },
      "references": [
        {
          "url": "https://git.kernel.org/stable/c/beb22ebf76c0415f22d2d0c3f1ff0627e7ae4a68"
        },
        {
          "url": "https://git.kernel.org/stable/c/1a8bab5ceee1a42a78de12d3d69f67516a20588e"
        },
        {
          "url": "https://git.kernel.org/stable/c/1889a9156553f0692acd57caf15e877baace1a01"
        },
        {
          "url": "https://git.kernel.org/stable/c/d19385624bdfb577db9c94bb8879992fd5e17bcd"
        },
        {
          "url": "https://git.kernel.org/stable/c/80e0d353c86a9a168ad6d213f494796294381538"
        }
      ],
      "title": "platform/x86: ISST: Validate level in perf mask ioctls",
      "x_generator": {
        "engine": "bippy-1.2.0"
      }
    }
  },
  "cveMetadata": {
    "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
    "assignerShortName": "Linux",
    "cveId": "CVE-2026-89443",
    "datePublished": "2026-09-11T19:43:11.407Z",
    "dateReserved": "2026-09-11T19:38:34.704Z",
    "dateUpdated": "2026-10-19T08:46:52.766Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2"
}


Log in or create an account to share your comment.




Tags
Taxonomy of the tags.




Sightings

Author Source Type Date

Nomenclature

  • Seen: The vulnerability was mentioned, discussed, or seen somewhere by the user.
  • Confirmed: The vulnerability is confirmed from an analyst perspective.
  • Published Proof of Concept: A public proof of concept is available for this vulnerability.
  • Exploited: This vulnerability was exploited and seen by the user reporting the sighting.
  • Patched: This vulnerability was successfully patched by the user reporting the sighting.
  • Not exploited: This vulnerability was not exploited or seen by the user reporting the sighting.
  • Not confirmed: The user expresses doubt about the veracity of the vulnerability.
  • Not patched: This vulnerability was not successfully patched by the user reporting the sighting.