{
  "schema_version": "1.6.1",
  "id": "RPI-CVE-2026-93191",
  "modified": "2026-10-07T17:22:01Z",
  "upstream": [
    "CVE-2026-93191"
  ],
  "published": "2026-09-17T16:10:40Z",
  "summary": "smack: fix incorrect task context in smack_msg_queue_msgrcv",
  "details": "In the Linux kernel, the following vulnerability has been resolved:\n\nsmack: fix incorrect task context in smack_msg_queue_msgrcv\n\nThe smack_msg_queue_msgrcv() function incorrectly checks\nthe permissions of the 'current' task instead of the\n'target' task.\n\nIn the msgsnd() syscall path, if a receiver is already waiting,\nthe pipelined_send() optimization is used to push the message\ndirectly to the receiver task:\n\n    ipc/msg.c`pipelined_send():\n    ` smp_store_release(&msr->r_msg, msg)\n\nIn this case, the 'sender' (current) task performs the check\non behalf of the 'receiver' task (msr->r_tsk, passed as the\n'target' parameter):\n\n  ipc/msg.c`pipelined_send():\n  ` security_msg_queue_msgrcv(,, target := msr->r_tsk,,)\n\nHowever, smack_msg_queue_msgrcv() ignores the 'target' and\nchecks 'current':\n\n  smack_msg_queue_msgrcv(\u2026)\n  ` smk_curacc_msq(isp, MAY_READWRITE); // current task\n\n'current' MAY satisfy smack_msg_queue_msgrcv r/w requirement,\nbut 'target' (the receiver task) might NOT;\nas a result, an unauthorized receiver gets the message,\nviolating MAC policy.\n\nTest:\n1) create a sysv message queue with label \u201cfoo\u201d\n2) echo \"bar foo r\" >/smack/load2\n3) msgrcv(,,,0,MSG_NOERROR) in \"bar\"-labeled task.\n    The task is waiting for the messages ...\n4) msgsnd() from a \"foo\"-labeled task:\n\"bar\"-labeled task gets the message.\n\nThis patch fixes the issue by checking permission on the\n'target' task instead of 'current'.\n\n(2008-02-04, Casey Schaufler)",
  "affected": [
    {
      "package": {
        "ecosystem": "Raspberry Pi OS:12",
        "name": "linux"
      },
      "versions": [
        "1:6.1.47-1+rpt4"
      ],
      "ecosystem_specific": {
        "binaries": [
          {
            "binary_name": "linux-image-6.1.0-rpi3-rpi-2712",
            "binary_version": "1:6.1.47-1+rpt4"
          },
          {
            "binary_name": "linux-image-6.1.0-rpi3-rpi-v6",
            "binary_version": "1:6.1.47-1+rpt4"
          },
          {
            "binary_name": "linux-image-6.1.0-rpi3-rpi-v7",
            "binary_version": "1:6.1.47-1+rpt4"
          },
          {
            "binary_name": "linux-image-6.1.0-rpi3-rpi-v7l",
            "binary_version": "1:6.1.47-1+rpt4"
          },
          {
            "binary_name": "linux-image-6.1.0-rpi3-rpi-v8",
            "binary_version": "1:6.1.47-1+rpt4"
          }
        ]
      },
      "database_specific": {
        "per_version": {
          "1:6.1.47-1+rpt4": {
            "linux_commit": "655fc658a15ae7a6f37103754adb39ba52a9a14e",
            "upstream_version": "6.1.47",
            "assessment": "commit ancestry (strak rule)",
            "upstream_fixed": "6.1.188",
            "compiled_filter": false
          }
        }
      }
    }
  ],
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://www.cve.org/CVERecord?id=CVE-2026-93191"
    },
    {
      "type": "FIX",
      "url": "https://git.kernel.org/stable/c/4e49f997ef0c569e09b42aab6bd38c7c54ea095d"
    },
    {
      "type": "FIX",
      "url": "https://git.kernel.org/stable/c/dbece6c2f80b0470d8d99d7a016827dce99ed6e3"
    },
    {
      "type": "FIX",
      "url": "https://git.kernel.org/stable/c/7be4bd21c50afa83c93799b0f16cf5bfa493194e"
    },
    {
      "type": "FIX",
      "url": "https://git.kernel.org/stable/c/ec47f4177046dfaaf1cebb15f4d2e7b543475daf"
    },
    {
      "type": "FIX",
      "url": "https://git.kernel.org/stable/c/e35dc5a4ed6d1e536382d80c685187511ff248a1"
    },
    {
      "type": "FIX",
      "url": "https://git.kernel.org/stable/c/c2ab27c2e11591524b1378c24ad18882a425d1fa"
    },
    {
      "type": "FIX",
      "url": "https://git.kernel.org/stable/c/d02c55e3ea82e41ea2c2026e08201e5daa4d0cfe"
    },
    {
      "type": "FIX",
      "url": "https://git.kernel.org/stable/c/fba3d32825f4bbc8e20f0cdc3b14df57965b8fe5"
    }
  ],
  "database_specific": {
    "source": "https://git.kernel.org/pub/scm/linux/security/vulns.git",
    "upstream_modified": "2026-09-17T16:10:40Z"
  }
}