CVE-2026-99024 affecting package kernel 6.6.157.1-1

{
  "id": "8b35f68826e75f3b162c5dc240721a0b6325727c143264424eb217af0a0cc7f1",
  "url": "https://osv.dev/vulnerability/AZL-110876",
  "method": "structured",
  "payload": {
    "kind": "advisory",
    "title": "CVE-2026-99024 affecting package kernel 6.6.157.1-1",
    "summary": "In the Linux kernel, the following vulnerability has been resolved: optee: register TEE devices only once fully initialized optee_probe() called tee_device_register() on both the client and the supplicant device before the rest of struct optee had been initialized. tee_device_register() calls cdev_device_add(), which does two things at once: it creates /dev/tee0 and /dev/teepriv0, and it links the device into the tee class so that class_find_device() can find it. From that moment on the device is reachable both from user space via tee_open() and from kernel space via tee_client_open_context(). The only gate in teedev_open() is tee_device_get(), which merely checks that teedev->desc is non-NULL, which was already set by tee_device_alloc(). Therefore, there is effectively no gate at all. A context opened in that window can run against a struct optee where - optee->call_queue.mutex is not initialized by optee_cq_init() - optee->supp mutex and completions is not initialized by optee_supp_init() - optee->rpmb_dev_mutex is not initialized yet, - the message argument cache is not initialized by optee_shm_arg_cache_init() - optee->ctx is still NULL Any open session or invoke during this window takes uninitialized mutexes and dereferences a NULL pointer. Fix it by moving both tee_device_register() calls down to the point where all of struct optee is set up. [JW: adding fixes and cc]",
    "evidence": "osv:AZL-110876",
    "products": [
      {
        "name": {
          "value": "kernel",
          "evidence": "/affected/0/package/name"
        },
        "prerequisites": [],
        "fixed_versions": [],
        "affected_versions": []
      }
    ],
    "severity": "unknown",
    "structured": {
      "id": "AZL-110876",
      "aliases": [
        "AZL-110876"
      ],
      "affected": [
        {
          "ranges": [
            {
              "type": "ECOSYSTEM",
              "events": [
                {
                  "introduced": "0"
                },
                {
                  "last_affected": "6.6.157.1-1"
                }
              ]
            }
          ],
          "package": {
            "name": "kernel",
            "purl": "pkg:rpm/azure-linux/kernel",
            "ecosystem": "Azure Linux:3"
          },
          "database_specific": {
            "source": "https://github.com/microsoft/AzureLinuxVulnerabilityData/blob/main/osv/AZL-110876.json"
          }
        }
      ],
      "modified": "2026-10-27T05:36:16Z",
      "provider": "osv",
      "upstream": [
        "CVE-2026-99024"
      ],
      "references": [
        "https://nvd.nist.gov/vuln/detail/CVE-2026-99024"
      ]
    },
    "related_cves": [
      {
        "value": "CVE-2026-99024",
        "evidence": "/upstream"
      }
    ],
    "security_relevant": true,
    "severity_evidence": null
  },
  "source_id": "core-osv",
  "document_id": 460655,
  "published_at": "2026-10-23T13:17:25+00:00"
}