{
  "threat_severity" : "Important",
  "public_date" : "2026-07-04T00:00:00Z",
  "bugzilla" : {
    "description" : "kernel: KVM: x86: Fix shadow paging use-after-free due to unexpected role",
    "id" : "2497033",
    "url" : "https://bugzilla.redhat.com/show_bug.cgi?id=2497033"
  },
  "cvss3" : {
    "cvss3_base_score" : "7.8",
    "cvss3_scoring_vector" : "CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:C/C:H/I:H/A:H",
    "status" : "verified"
  },
  "cwe" : "CWE-825",
  "details" : [ "In the Linux kernel, the following vulnerability has been resolved:\nKVM: x86: Fix shadow paging use-after-free due to unexpected role\nCommit 0cb2af2ea66ad (\"KVM: x86: Fix shadow paging use-after-free due\nto unexpected GFN\") fixed a shadow paging mismatch between stored and\ncomputed GFNs; the bug could be triggered by changing a PDE mapping from\noutside the guest, and then deleting a memslot.  The rmap_remove()\ncall would miss entries created after the PDE change because the GFN\nof the leaf SPTE does not match the GFN of the struct kvm_mmu_page.\nA similar hole however remains if the modified PDE points to a non-leaf\npage.  In this case the gfn can be made to match, but the role does not\nmatch: the original large 2MB page creates a kvm_mmu_page with direct=1,\nwhile the new 4KB needs a kvm_mmu_page with direct=0.  However,\nkvm_mmu_get_child_sp() does not compare the role, and therefore reuses\nthe page.\nThe next step is installing a leaf (4KB) SPTE on the new path which\nrecords an rmap entry under the gfn resolved by the walk.  But when\nthat child is zapped its parent kvm_mmu_page has direct=1 and\nkvm_mmu_page_get_gfn() computes the gfn for the 4KB page as\nsp->gfn + index instead of using sp->shadowed_translation[] (or sp->gfns[]\nin older kernels).  It therefore fails to remove the recorded entry.\nWhen the memslot is dropped the shadow page is freed but the rmap\nentry survives, as in the scenario that was already fixed.  Code that\nlater walks that gfn (dirty logging, MMU notifier invalidation, and\nso on) dereferences an sptep that lies in the freed page, causing the\nuse-after-free.", "A flaw was found in the Linux kernel's Kernel-based Virtual Machine (KVM) x86 shadow paging mechanism. This vulnerability occurs when a host page directory entry (PDE) mapping is changed from within the guest, leading to an unexpected role mismatch in shadow paging. This mismatch can cause a use-after-free condition, where the system attempts to access memory that has already been released. Such a condition can lead to system instability, denial of service, potentially the execution of arbitrary code or guest-to-host escape." ],
  "statement" : "This is an Important flaw in the KVM x86 shadow paging mechanism where an attacker with privileged access inside the guest VM could trigger a use-after-free condition by manipulating page directory entries on the host. This could lead to system instability, denial of service, or potentially arbitrary code execution on the host.\nIn Red Hat Enterprise Linux 7, nested virtualization for KVM is a Technology Preview feature and the nested parameter defaults to 0 (disabled) for both kvm_intel and kvm_amd.",
  "affected_release" : [ {
    "product_name" : "Red Hat Enterprise Linux 10",
    "release_date" : "2026-07-09T00:00:00Z",
    "advisory" : "RHSA-2026:36956",
    "cpe" : "cpe:/o:redhat:enterprise_linux:10.2",
    "package" : "kernel-0:6.12.0-211.32.1.el10_2"
  }, {
    "product_name" : "Red Hat Enterprise Linux 10.0 Extended Update Support",
    "release_date" : "2026-07-14T00:00:00Z",
    "advisory" : "RHSA-2026:39371",
    "cpe" : "cpe:/o:redhat:enterprise_linux_eus:10.0",
    "package" : "kernel-0:6.12.0-55.88.1.el10_0"
  }, {
    "product_name" : "Red Hat Enterprise Linux 8",
    "release_date" : "2026-07-14T00:00:00Z",
    "advisory" : "RHSA-2026:39082",
    "cpe" : "cpe:/a:redhat:enterprise_linux:8::nfv",
    "package" : "kernel-rt-0:4.18.0-553.143.1.rt7.484.el8_10"
  }, {
    "product_name" : "Red Hat Enterprise Linux 8",
    "release_date" : "2026-07-14T00:00:00Z",
    "advisory" : "RHSA-2026:39083",
    "cpe" : "cpe:/o:redhat:enterprise_linux:8",
    "package" : "kernel-0:4.18.0-553.143.1.el8_10"
  }, {
    "product_name" : "Red Hat Enterprise Linux 8.8 Telecommunications Update Service",
    "release_date" : "2026-07-17T00:00:00Z",
    "advisory" : "RHSA-2026:41229",
    "cpe" : "cpe:/o:redhat:rhel_tus:8.8",
    "package" : "kernel-0:4.18.0-477.154.1.el8_8"
  }, {
    "product_name" : "Red Hat Enterprise Linux 8.8 Update Services for SAP Solutions",
    "release_date" : "2026-07-17T00:00:00Z",
    "advisory" : "RHSA-2026:41229",
    "cpe" : "cpe:/o:redhat:rhel_e4s:8.8",
    "package" : "kernel-0:4.18.0-477.154.1.el8_8"
  }, {
    "product_name" : "Red Hat Enterprise Linux 9",
    "release_date" : "2026-07-09T00:00:00Z",
    "advisory" : "RHSA-2026:36957",
    "cpe" : "cpe:/a:redhat:enterprise_linux:9",
    "package" : "kernel-0:5.14.0-687.24.1.el9_8"
  }, {
    "product_name" : "Red Hat Enterprise Linux 9",
    "release_date" : "2026-07-09T00:00:00Z",
    "advisory" : "RHSA-2026:36957",
    "cpe" : "cpe:/o:redhat:enterprise_linux:9",
    "package" : "kernel-0:5.14.0-687.24.1.el9_8"
  }, {
    "product_name" : "Red Hat Enterprise Linux 9.2 Update Services for SAP Solutions",
    "release_date" : "2026-07-15T00:00:00Z",
    "advisory" : "RHSA-2026:40082",
    "cpe" : "cpe:/a:redhat:rhel_e4s:9.2",
    "package" : "kernel-0:5.14.0-284.181.1.el9_2"
  }, {
    "product_name" : "Red Hat Enterprise Linux 9.2 Update Services for SAP Solutions",
    "release_date" : "2026-07-15T00:00:00Z",
    "advisory" : "RHSA-2026:39983",
    "cpe" : "cpe:/a:redhat:rhel_e4s:9.2::nfv",
    "package" : "kernel-rt-0:5.14.0-284.181.1.rt14.466.el9_2"
  }, {
    "product_name" : "Red Hat Enterprise Linux 9.4 Update Services for SAP Solutions",
    "release_date" : "2026-07-10T00:00:00Z",
    "advisory" : "RHSA-2026:37729",
    "cpe" : "cpe:/a:redhat:rhel_e4s:9.4",
    "package" : "kernel-0:5.14.0-427.137.1.el9_4"
  }, {
    "product_name" : "Red Hat Enterprise Linux 9.6 Extended Update Support",
    "release_date" : "2026-07-13T00:00:00Z",
    "advisory" : "RHSA-2026:38902",
    "cpe" : "cpe:/a:redhat:rhel_eus:9.6",
    "package" : "kernel-0:5.14.0-570.127.1.el9_6"
  }, {
    "product_name" : "Red Hat OpenShift Container Platform 4.20",
    "release_date" : "2026-07-21T00:00:00Z",
    "advisory" : "RHSA-2026:40787",
    "cpe" : "cpe:/a:redhat:openshift:4.20::el9",
    "package" : "rhcos-4.20.9.6.202607151937-0"
  }, {
    "product_name" : "Red Hat OpenShift Container Platform 4.21",
    "release_date" : "2026-07-21T00:00:00Z",
    "advisory" : "RHSA-2026:40779",
    "cpe" : "cpe:/a:redhat:openshift:4.21::el9",
    "package" : "rhcos-4.21.9.6.202607151836-0"
  }, {
    "product_name" : "Red Hat OpenShift Container Platform 4.22",
    "release_date" : "2026-07-21T00:00:00Z",
    "advisory" : "RHSA-2026:40764",
    "cpe" : "cpe:/a:redhat:openshift:4.22::el9",
    "package" : "rhcos-4.22.9.8.202607152026-0"
  } ],
  "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" : "Out of support scope",
    "package_name" : "kernel",
    "cpe" : "cpe:/o:redhat:enterprise_linux:7",
    "impact" : "moderate"
  }, {
    "product_name" : "Red Hat Enterprise Linux 7",
    "fix_state" : "Out of support scope",
    "package_name" : "kernel-rt",
    "cpe" : "cpe:/o:redhat:enterprise_linux:7",
    "impact" : "moderate"
  }, {
    "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 Enterprise Linux for NVIDIA 26",
    "fix_state" : "Not affected",
    "package_name" : "kernel",
    "cpe" : "cpe:/a:redhat:enterprise_linux_nvidia:"
  } ],
  "references" : [ "https://www.cve.org/CVERecord?id=CVE-2026-53359\nhttps://nvd.nist.gov/vuln/detail/CVE-2026-53359\nhttps://lore.kernel.org/linux-cve-announce/2026070403-CVE-2026-53359-4f57@gregkh/T\nhttps://www.openwall.com/lists/oss-security/2026/07/06/7" ],
  "csaw" : true,
  "name" : "CVE-2026-53359",
  "mitigation" : {
    "value" : "This vulnerability can be mitigated by disabling nested virtualization. Create a file in `/etc/modprobe.d/` with a descriptive name, such as `cve-2026-53359-mitigation.conf`. In that file, disable nested virtualization for the `kvm_intel` and `kvm_amd` kernel modules:\n```\noptions kvm-intel nested=0\noptions kvm-amd nested=0\n```\nUse `lsmod` to determine if either module is already loaded. If so, remove loaded modules with `modprobe -r`. To validate that nested virtualization is disabled, read the files `/sys/module/kvm_intel/parameters/nested` and `/sys/module/kvm_amd/parameters/nested`. If these modules are loaded, those files should read `N` to indicate that the feature is disabled.\nIn OpenShift 4, a MachineConfig can be utilized to create a modprobe configuration allowing control of the module on applicable nodes. See the following article for an example.\nhttps://access.redhat.com/solutions/6979679",
    "lang" : "en:us"
  }
}