{
  "threat_severity" : "Moderate",
  "public_date" : "2024-04-24T00:00:00Z",
  "bugzilla" : {
    "description" : "kernel: af_unix: Fix garbage collector racing against connect()",
    "id" : "2277171",
    "url" : "https://bugzilla.redhat.com/show_bug.cgi?id=2277171"
  },
  "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-362",
  "details" : [ "In the Linux kernel, the following vulnerability has been resolved:\naf_unix: Fix garbage collector racing against connect()\nGarbage collector does not take into account the risk of embryo getting\nenqueued during the garbage collection. If such embryo has a peer that\ncarries SCM_RIGHTS, two consecutive passes of scan_children() may see a\ndifferent set of children. Leading to an incorrectly elevated inflight\ncount, and then a dangling pointer within the gc_inflight_list.\nsockets are AF_UNIX/SOCK_STREAM\nS is an unconnected socket\nL is a listening in-flight socket bound to addr, not in fdtable\nV's fd will be passed via sendmsg(), gets inflight count bumped\nconnect(S, addr)sendmsg(S, [V]); close(V)__unix_gc()\n----------------------------------------------------\nNS = unix_create1()\nskb1 = sock_wmalloc(NS)\nL = unix_find_other(addr)\nunix_state_lock(L)\nunix_peer(S) = NS\n// V count=1 inflight=0\nNS = unix_peer(S)\nskb2 = sock_alloc()\nskb_queue_tail(NS, skb2[V])\n// V became in-flight\n// V count=2 inflight=1\nclose(V)\n// V count=1 inflight=1\n// GC candidate condition met\nfor u in gc_inflight_list:\nif (total_refs == inflight_refs)\nadd u to gc_candidates\n// gc_candidates={L, V}\nfor u in gc_candidates:\nscan_children(u, dec_inflight)\n// embryo (skb1) was not\n// reachable from L yet, so V's\n// inflight remains unchanged\n__skb_queue_tail(L, skb1)\nunix_state_unlock(L)\nfor u in gc_candidates:\nif (u.inflight)\nscan_children(u, inc_inflight_move_tail)\n// V count=1 inflight=2 (!)\nIf there is a GC-candidate listening socket, lock/unlock its state. This\nmakes GC wait until the end of any ongoing connect() to that socket. After\nflipping the lock, a possibly SCM-laden embryo is already enqueued. And if\nthere is another embryo coming, it can not possibly carry SCM_RIGHTS. At\nthis point, unix_inflight() can not happen because unix_gc_lock is already\ntaken. Inflight graph remains unaffected.", "A flaw was found in the Linux kernel, where the management of inter-process communication uses AF_UNIX sockets. The issue arises from a race condition where a partially initialized socket with specific permissions carrying SCM_RIGHTS is improperly handled during garbage collection. This situation leads to an incorrect count of active sockets, potentially causing resources to remain unaccounted for and never released." ],
  "statement" : "Red Hat rates the security impact of this vulnerability as Moderate due to the worst-case scenario resulting in a resource consumption attack. Considering this is a timing attack and is hard to replicate outside of very controlled environments, the vulnerability is not rated higher.",
  "affected_release" : [ {
    "product_name" : "Red Hat Enterprise Linux 8",
    "release_date" : "2024-09-24T00:00:00Z",
    "advisory" : "RHSA-2024:7001",
    "cpe" : "cpe:/a:redhat:enterprise_linux:8::nfv",
    "package" : "kernel-rt-0:4.18.0-553.22.1.rt7.363.el8_10"
  }, {
    "product_name" : "Red Hat Enterprise Linux 8",
    "release_date" : "2024-09-24T00:00:00Z",
    "advisory" : "RHSA-2024:7000",
    "cpe" : "cpe:/o:redhat:enterprise_linux:8",
    "package" : "kernel-0:4.18.0-553.22.1.el8_10"
  }, {
    "product_name" : "Red Hat Enterprise Linux 8.6 Advanced Mission Critical Update Support",
    "release_date" : "2024-10-02T00:00:00Z",
    "advisory" : "RHSA-2024:7486",
    "cpe" : "cpe:/o:redhat:rhel_aus:8.6",
    "package" : "kernel-0:4.18.0-372.125.1.el8_6"
  }, {
    "product_name" : "Red Hat Enterprise Linux 8.6 Telecommunications Update Service",
    "release_date" : "2024-10-02T00:00:00Z",
    "advisory" : "RHSA-2024:7486",
    "cpe" : "cpe:/o:redhat:rhel_tus:8.6",
    "package" : "kernel-0:4.18.0-372.125.1.el8_6"
  }, {
    "product_name" : "Red Hat Enterprise Linux 8.6 Update Services for SAP Solutions",
    "release_date" : "2024-10-02T00:00:00Z",
    "advisory" : "RHSA-2024:7486",
    "cpe" : "cpe:/o:redhat:rhel_e4s:8.6",
    "package" : "kernel-0:4.18.0-372.125.1.el8_6"
  }, {
    "product_name" : "Red Hat Enterprise Linux 8.8 Extended Update Support",
    "release_date" : "2024-09-24T00:00:00Z",
    "advisory" : "RHSA-2024:6993",
    "cpe" : "cpe:/o:redhat:rhel_eus:8.8",
    "package" : "kernel-0:4.18.0-477.74.1.el8_8"
  }, {
    "product_name" : "Red Hat Enterprise Linux 9",
    "release_date" : "2024-10-30T00:00:00Z",
    "advisory" : "RHSA-2024:8617",
    "cpe" : "cpe:/a:redhat:enterprise_linux:9",
    "package" : "kernel-0:5.14.0-427.42.1.el9_4"
  }, {
    "product_name" : "Red Hat Enterprise Linux 9",
    "release_date" : "2024-10-30T00:00:00Z",
    "advisory" : "RHSA-2024:8617",
    "cpe" : "cpe:/o:redhat:enterprise_linux:9",
    "package" : "kernel-0:5.14.0-427.42.1.el9_4"
  }, {
    "product_name" : "Red Hat Enterprise Linux 9.2 Extended Update Support",
    "release_date" : "2024-07-24T00:00:00Z",
    "advisory" : "RHSA-2024:4823",
    "cpe" : "cpe:/a:redhat:rhel_eus:9.2",
    "package" : "kernel-0:5.14.0-284.75.1.el9_2"
  }, {
    "product_name" : "Red Hat Enterprise Linux 9.2 Extended Update Support",
    "release_date" : "2024-07-24T00:00:00Z",
    "advisory" : "RHSA-2024:4831",
    "cpe" : "cpe:/a:redhat:rhel_eus:9.2::nfv",
    "package" : "kernel-rt-0:5.14.0-284.75.1.rt14.360.el9_2"
  } ],
  "package_state" : [ {
    "product_name" : "Red Hat Enterprise Linux 6",
    "fix_state" : "Out of support scope",
    "package_name" : "kernel",
    "cpe" : "cpe:/o:redhat:enterprise_linux:6"
  }, {
    "product_name" : "Red Hat Enterprise Linux 7",
    "fix_state" : "Out of support scope",
    "package_name" : "kernel",
    "cpe" : "cpe:/o:redhat:enterprise_linux:7"
  }, {
    "product_name" : "Red Hat Enterprise Linux 7",
    "fix_state" : "Out of support scope",
    "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"
  } ],
  "references" : [ "https://www.cve.org/CVERecord?id=CVE-2024-26923\nhttps://nvd.nist.gov/vuln/detail/CVE-2024-26923\nhttps://lore.kernel.org/linux-cve-announce/2024042418-CVE-2024-26923-f7f6@gregkh/T" ],
  "name" : "CVE-2024-26923",
  "mitigation" : {
    "value" : "There are no known mitigations to this issue and updating to the latest Linux kernel version is recommended to address this vulnerability​.",
    "lang" : "en:us"
  },
  "csaw" : false
}