{
  "affected": [
    {
      "ranges": [
        {
          "events": [
            {
              "introduced": "bdabad3e363d825ddf9679dd431cca0b2c30f881"
            },
            {
              "fixed": "2aa4c12723fe432e623462a3be42a197a128722b"
            },
            {
              "fixed": "03bfa95e452e2b6ccd76a332060ae4feaf5ad84d"
            },
            {
              "fixed": "474293d90880622fde9d2430fb0165767090f7b3"
            },
            {
              "fixed": "2047c2aa0963bb2872fd722300a15bcb441a4c00"
            },
            {
              "fixed": "7de2d447072be3b1a76793f034432338fc9c494b"
            },
            {
              "fixed": "ab269990ed58143a92a263be1bee626d82ac03da"
            },
            {
              "fixed": "3b20ec8f31e8a6a6782243f473b0abd3463621df"
            },
            {
              "fixed": "a2171131ecda1ed61a594a1eb715e75fdad0fef5"
            }
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "type": "GIT"
        }
      ]
    },
    {
      "package": {
        "ecosystem": "Linux",
        "name": "Kernel"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "4.7.0"
            },
            {
              "fixed": "5.10.259"
            }
          ],
          "type": "ECOSYSTEM"
        },
        {
          "events": [
            {
              "introduced": "5.11.0"
            },
            {
              "fixed": "5.15.210"
            }
          ],
          "type": "ECOSYSTEM"
        },
        {
          "events": [
            {
              "introduced": "5.16.0"
            },
            {
              "fixed": "6.1.176"
            }
          ],
          "type": "ECOSYSTEM"
        },
        {
          "events": [
            {
              "introduced": "6.2.0"
            },
            {
              "fixed": "6.6.143"
            }
          ],
          "type": "ECOSYSTEM"
        },
        {
          "events": [
            {
              "introduced": "6.7.0"
            },
            {
              "fixed": "6.12.94"
            }
          ],
          "type": "ECOSYSTEM"
        },
        {
          "events": [
            {
              "introduced": "6.13.0"
            },
            {
              "fixed": "6.18.36"
            }
          ],
          "type": "ECOSYSTEM"
        },
        {
          "events": [
            {
              "introduced": "6.19.0"
            },
            {
              "fixed": "7.0.13"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "database_specific": {
    "cna_assigner": "Linux",
    "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/52xxx/CVE-2026-52947.json"
  },
  "details": "In the Linux kernel, the following vulnerability has been resolved:\n\nnet: qrtr: fix refcount saturation and potential UAF in qrtr_port_remove\n\nIn qrtr_port_remove(), the socket reference count is decremented via\n__sock_put() before the port is removed from the qrtr_ports XArray and\nbefore the RCU grace period elapses.\n\nThis breaks the fundamental RCU update paradigm. It exposes a race\nwindow where a concurrent RCU reader (such as qrtr_reset_ports() or\nqrtr_port_lookup()) can obtain a pointer to the socket from the XArray,\nand attempt to call sock_hold() on a socket whose reference count has\nalready dropped to zero.\n\nThis exact race condition was hit during syzkaller fuzzing, leading to\nthe following refcount saturation warning and a potential Use-After-Free:\n\n  refcount_t: saturated; leaking memory.\n  WARNING: CPU: 3 PID: 1273 at lib/refcount.c:22 refcount_warn_saturate+0xae/0x1d0\n  Modules linked in: qrtr(+) bochs drm_shmem_helper ...\n  Call Trace:\n   \u003cTASK\u003e\n   qrtr_reset_ports net/qrtr/af_qrtr.c:768 [inline] [qrtr]\n   __qrtr_bind.isra.0+0x48b/0x570 net/qrtr/af_qrtr.c:805 [qrtr]\n   qrtr_bind+0x17d/0x210 net/qrtr/af_qrtr.c:901 [qrtr]\n   kernel_bind+0xe4/0x120 net/socket.c:3592\n   qrtr_ns_init+0x1a6/0x380 net/qrtr/ns.c:715 [qrtr]\n   qrtr_proto_init+0x3b/0xff0 net/qrtr/af_qrtr.c:169 [qrtr]\n   do_one_initcall+0xf5/0x5e0 init/main.c:1283\n   ...\n   \u003c/TASK\u003e\n\nFix this by deferring the reference count decrement until after the\nxa_erase() and the synchronize_rcu() complete.\n\n(Note: The v1 of this patch incorrectly replaced __sock_put() with\nsock_put(). As Simon Horman pointed out, the callers of qrtr_port_remove()\nstill hold a reference to the socket, so freeing the socket memory here\nwould lead to a subsequent UAF in the caller. Thus, the __sock_put() is\nkept, but only repositioned to close the RCU race.)",
  "id": "CVE-2026-52947",
  "modified": "2026-07-12T03:54:50.950990991Z",
  "published": "2026-06-24T16:26:05.062Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/03bfa95e452e2b6ccd76a332060ae4feaf5ad84d"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/2047c2aa0963bb2872fd722300a15bcb441a4c00"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/2aa4c12723fe432e623462a3be42a197a128722b"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/3b20ec8f31e8a6a6782243f473b0abd3463621df"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/474293d90880622fde9d2430fb0165767090f7b3"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/7de2d447072be3b1a76793f034432338fc9c494b"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/a2171131ecda1ed61a594a1eb715e75fdad0fef5"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/ab269990ed58143a92a263be1bee626d82ac03da"
    },
    {
      "type": "ADVISORY",
      "url": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/52xxx/CVE-2026-52947.json"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-52947"
    },
    {
      "type": "PACKAGE",
      "url": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git"
    }
  ],
  "schema_version": "1.7.5",
  "severity": [
    {
      "score": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H",
      "type": "CVSS_V3"
    }
  ],
  "summary": "net: qrtr: fix refcount saturation and potential UAF in qrtr_port_remove"
}