CVE-2026-80954 (GCVE-0-2026-80954)
Vulnerability from cvelistv5
Published
2026-09-11 19:42
Modified
2026-10-19 08:45
Severity ?
7.8 (High) - CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Summary
In the Linux kernel, the following vulnerability has been resolved: i3c: Fix unlocked dereference of dev->desc in i3c_device_get_supported_xfer_mode() i3c_device_get_supported_xfer_mode() uses dev->desc to obtain the master controller. However, dev->desc must not be dereferenced unless bus->lock is held, and this function does not take that lock. The function only needs access to the master controller associated with the device's bus. Use dev->bus instead, which is always valid for the lifetime of the device and does not require dereferencing dev->desc.
References
Impacted products
Vendor Product Version
Linux Linux Version: 256a21743d911f94ce92fe28f793cd586f3860b2
Version: 256a21743d911f94ce92fe28f793cd586f3860b2
 Create a notification for this product.
Show details on NVD website

To clipboard 

{
  "containers": {
    "cna": {
      "affected": [
        {
          "defaultStatus": "unaffected",
          "product": "Linux",
          "programFiles": [
            "drivers/i3c/device.c",
            "drivers/i3c/internals.h",
            "drivers/i3c/master.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "lessThan": "251db58324ea4792c3f9f692ab09be148e051969",
              "status": "affected",
              "version": "256a21743d911f94ce92fe28f793cd586f3860b2",
              "versionType": "git"
            },
            {
              "lessThan": "8bed7f4fa710914b7f05fd59998316bfb4d43385",
              "status": "affected",
              "version": "256a21743d911f94ce92fe28f793cd586f3860b2",
              "versionType": "git"
            }
          ]
        },
        {
          "defaultStatus": "affected",
          "product": "Linux",
          "programFiles": [
            "drivers/i3c/device.c",
            "drivers/i3c/internals.h",
            "drivers/i3c/master.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "status": "affected",
              "version": "6.19"
            },
            {
              "lessThan": "6.19",
              "status": "unaffected",
              "version": "0",
              "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": "7.2.4",
                  "versionStartIncluding": "6.19",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "7.3",
                  "versionStartIncluding": "6.19",
                  "vulnerable": true
                }
              ],
              "negate": false,
              "operator": "OR"
            }
          ]
        }
      ],
      "descriptions": [
        {
          "lang": "en",
          "value": "In the Linux kernel, the following vulnerability has been resolved:\n\ni3c: Fix unlocked dereference of dev-\u003edesc in i3c_device_get_supported_xfer_mode()\n\ni3c_device_get_supported_xfer_mode() uses dev-\u003edesc to obtain the\nmaster controller.  However, dev-\u003edesc must not be dereferenced unless\nbus-\u003elock is held, and this function does not take that lock.\n\nThe function only needs access to the master controller associated with\nthe device\u0027s bus.  Use dev-\u003ebus instead, which is always valid for the\nlifetime of the device and does not require dereferencing dev-\u003edesc."
        }
      ],
      "metrics": [
        {
          "cvssV3_1": {
            "baseScore": 7.8,
            "baseSeverity": "HIGH",
            "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H",
            "version": "3.1"
          },
          "scenarios": [
            {
              "lang": "en",
              "value": "AV:L - The unlocked desc dereference is reached from local IIO sysfs reads of an I3C-backed MMC5633 magnetometer (in_magn_*_raw/in_temp_raw via iio_read_channel_info) and from /dev/iio:deviceN; I3C is an on-board host bus with no network or Bluetooth packet path.\nAC:L - A local attacker can loop those IIO reads while concurrently forcing Dynamic Address Assignment, which replaces and kfree()s i3c_dev_desc (hot-join, MIPI I3C HCI/Renesas resume re-DAA, or sysfs do_daa). The attacker drives the unlocked-read side and can retry until it races with DAA.\nPR:L - IIO channel attributes are created 0444/0644 and iio_read_channel_info performs no capability check, so an unprivileged local user on Android, automotive, or embedded I3C boards can invoke mmc5633_read_raw without init-namespace root.\nUI:N - The attacker performs their own sysfs or IIO chardev reads against an already-present I3C device; no separate victim action such as plugging hardware or mounting a filesystem is required.\nS:U - The use-after-free corrupts an i3c_dev_desc in the host kernel heap and does not cross a VM, IOMMU, or sandbox boundary.\nC:H - Unlocked load of dev-\u003edesc races with DAA\u0027s i3c_master_free_i3c_dev(), so i3c_dev_get_master() walks a freed descriptor (common.master then this-\u003einfo.hdr_cap). Reclaiming that object yields a kernel read primitive; UAF is High confidentiality.\nI:H - A sprayed fake i3c_dev_desc lets the nested pointer walk interpret attacker-controlled heap as kernel objects, enabling further writes and control-flow hijack through the same freed slab; UAF is High integrity.\nA:H - Dereferencing a NULL or freed desc in i3c_dev_get_master() causes a kernel oops or panic even without a full exploit, so availability impact is High."
            }
          ]
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-10-19T08:45:38.169Z",
        "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "shortName": "Linux"
      },
      "references": [
        {
          "url": "https://git.kernel.org/stable/c/251db58324ea4792c3f9f692ab09be148e051969"
        },
        {
          "url": "https://git.kernel.org/stable/c/8bed7f4fa710914b7f05fd59998316bfb4d43385"
        }
      ],
      "title": "i3c: Fix unlocked dereference of dev-\u003edesc in i3c_device_get_supported_xfer_mode()",
      "x_generator": {
        "engine": "bippy-1.2.0"
      }
    }
  },
  "cveMetadata": {
    "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
    "assignerShortName": "Linux",
    "cveId": "CVE-2026-80954",
    "datePublished": "2026-09-11T19:42:23.169Z",
    "dateReserved": "2026-08-26T14:34:25.804Z",
    "dateUpdated": "2026-10-19T08:45:38.169Z",
    "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.