{
  "threat_severity" : "Important",
  "public_date" : "2026-07-19T00:00:00Z",
  "bugzilla" : {
    "description" : "kernel: nfsd: release layout stid on setlease failure",
    "id" : "2502239",
    "url" : "https://bugzilla.redhat.com/show_bug.cgi?id=2502239"
  },
  "cvss3" : {
    "cvss3_base_score" : "7.0",
    "cvss3_scoring_vector" : "CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H",
    "status" : "verified"
  },
  "cwe" : "CWE-825",
  "details" : [ "In the Linux kernel, the following vulnerability has been resolved:\nnfsd: release layout stid on setlease failure\nnfs4_alloc_stid() publishes the new stid into cl->cl_stateids via\nidr_alloc_cyclic() under cl_lock before returning to\nnfsd4_alloc_layout_stateid(). When nfsd4_layout_setlease() then\nfails, the error path frees the layout stateid directly with\nkmem_cache_free() without ever calling idr_remove(), leaving the\nIDR slot pointing at freed slab memory. Any subsequent IDR walker\n(states_show, client teardown) dereferences the dangling pointer.\nThe correct teardown for an IDR-published stid is nfs4_put_stid(),\nwhich removes the IDR slot under cl_lock, dispatches sc_free\n(nfsd4_free_layout_stateid) to release ls->ls_file via\nnfsd4_close_layout(), and drops the nfs4_file reference in its\ntail.\nA second issue blocks that switch: nfsd4_free_layout_stateid()\nunconditionally inspects ls->ls_fence_work via\ndelayed_work_pending() under ls_lock, but\nINIT_DELAYED_WORK(&ls->ls_fence_work, ...) currently runs only\nafter the setlease call. On the setlease-failure path the\ndestructor would touch an uninitialized delayed_work.\nnfsd4_alloc_layout_stateid()\nnfs4_alloc_stid()           /* idr_alloc_cyclic under cl_lock */\nnfsd4_layout_setlease()     /* fails */\nnfs4_put_stid()\nnfsd4_free_layout_stateid()\ndelayed_work_pending(&ls->ls_fence_work)  /* needs INIT */\nnfsd4_close_layout()  /* nfsd_file_put(ls->ls_file) */\nput_nfs4_file()\nFix by hoisting the ls_fenced / ls_fence_delay / INIT_DELAYED_WORK\ninitialization above the nfsd4_layout_setlease() call, and replace\nthe manual nfsd_file_put + put_nfs4_file + kmem_cache_free cleanup\nwith a single nfs4_put_stid(stp).", "A flaw was found in the Linux kernel's Network File System Daemon (nfsd). When a `setlease` operation fails, the system prematurely releases a layout state identifier. An attacker could exploit this by triggering the failure, leading to a use-after-free vulnerability. This could result in a system crash, causing a Denial of Service (DoS)." ],
  "affected_release" : [ {
    "product_name" : "Red Hat Enterprise Linux 10",
    "release_date" : "2026-09-01T00:00:00Z",
    "advisory" : "RHSA-2026:61887",
    "cpe" : "cpe:/o:redhat:enterprise_linux:10.2",
    "package" : "kernel-0:6.12.0-211.50.1.el10_2"
  }, {
    "product_name" : "Red Hat Enterprise Linux 8",
    "release_date" : "2026-09-03T00:00:00Z",
    "advisory" : "RHSA-2026:63013",
    "cpe" : "cpe:/a:redhat:enterprise_linux:8::nfv",
    "package" : "kernel-rt-0:4.18.0-553.159.1.rt7.500.el8_10"
  }, {
    "product_name" : "Red Hat Enterprise Linux 8",
    "release_date" : "2026-09-03T00:00:00Z",
    "advisory" : "RHSA-2026:63014",
    "cpe" : "cpe:/o:redhat:enterprise_linux:8",
    "package" : "kernel-0:4.18.0-553.159.1.el8_10"
  }, {
    "product_name" : "Red Hat Enterprise Linux 9",
    "release_date" : "2026-09-04T00:00:00Z",
    "advisory" : "RHSA-2026:63129",
    "cpe" : "cpe:/a:redhat:enterprise_linux:9",
    "package" : "kernel-0:5.14.0-687.44.1.el9_8"
  }, {
    "product_name" : "Red Hat Enterprise Linux 9",
    "release_date" : "2026-09-04T00:00:00Z",
    "advisory" : "RHSA-2026:63129",
    "cpe" : "cpe:/o:redhat:enterprise_linux:9",
    "package" : "kernel-0:5.14.0-687.44.1.el9_8"
  } ],
  "package_state" : [ {
    "product_name" : "Red Hat Enterprise Linux 6",
    "fix_state" : "Not affected",
    "package_name" : "kernel",
    "cpe" : "cpe:/o:redhat:enterprise_linux:6"
  }, {
    "product_name" : "Red Hat Enterprise Linux 7",
    "fix_state" : "Affected",
    "package_name" : "kernel",
    "cpe" : "cpe:/o:redhat:enterprise_linux:7"
  }, {
    "product_name" : "Red Hat Enterprise Linux 7",
    "fix_state" : "Affected",
    "package_name" : "kernel-rt",
    "cpe" : "cpe:/o:redhat:enterprise_linux:7"
  }, {
    "product_name" : "Red Hat Enterprise Linux 9",
    "fix_state" : "Affected",
    "package_name" : "kernel-rt",
    "cpe" : "cpe:/o:redhat:enterprise_linux:9"
  }, {
    "product_name" : "Red Hat Hardened Images",
    "fix_state" : "Not affected",
    "package_name" : "erlang27",
    "cpe" : "cpe:/a:redhat:hummingbird:1",
    "impact" : "important"
  } ],
  "references" : [ "https://www.cve.org/CVERecord?id=CVE-2026-53399\nhttps://nvd.nist.gov/vuln/detail/CVE-2026-53399\nhttps://lore.kernel.org/linux-cve-announce/2026071958-CVE-2026-53399-c8aa@gregkh/T" ],
  "name" : "CVE-2026-53399",
  "csaw" : false
}