{
  "threat_severity" : "Moderate",
  "public_date" : "2021-03-05T00:00:00Z",
  "bugzilla" : {
    "description" : "kernel: iscsi: unrestricted access to sessions and handles",
    "id" : "1930079",
    "url" : "https://bugzilla.redhat.com/show_bug.cgi?id=1930079"
  },
  "cvss3" : {
    "cvss3_base_score" : "4.4",
    "cvss3_scoring_vector" : "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:L",
    "status" : "verified"
  },
  "cwe" : "CWE-200",
  "details" : [ "An issue was discovered in the Linux kernel through 5.11.3. A kernel pointer leak can be used to determine the address of the iscsi_transport structure. When an iSCSI transport is registered with the iSCSI subsystem, the transport's handle is available to unprivileged users via the sysfs file system, at /sys/class/iscsi_transport/$TRANSPORT_NAME/handle. When read, the show_transport_handle function (in drivers/scsi/scsi_transport_iscsi.c) is called, which leaks the handle. This handle is actually the pointer to an iscsi_transport struct in the kernel module's global variables.", "A flaw was found in the way access to sessions and handles was handled in the iSCSI driver in the Linux kernel. A local user could use this flaw to leak iSCSI transport handle kernel address or end arbitrary iSCSI connections on the system." ],
  "acknowledgement" : "Red Hat would like to thank Adam Nichols (GRIMM) for reporting this issue.",
  "affected_release" : [ {
    "product_name" : "Red Hat Enterprise Linux 7",
    "release_date" : "2021-04-06T00:00:00Z",
    "advisory" : "RHSA-2021:1070",
    "cpe" : "cpe:/a:redhat:rhel_extras_rt:7",
    "package" : "kernel-rt-0:3.10.0-1160.24.1.rt56.1161.el7"
  }, {
    "product_name" : "Red Hat Enterprise Linux 7",
    "release_date" : "2021-04-08T00:00:00Z",
    "advisory" : "RHSA-2021:1071",
    "cpe" : "cpe:/o:redhat:enterprise_linux:7",
    "package" : "kernel-0:3.10.0-1160.24.1.el7"
  }, {
    "product_name" : "Red Hat Enterprise Linux 7.2 Advanced Update Support",
    "release_date" : "2021-04-20T00:00:00Z",
    "advisory" : "RHSA-2021:1289",
    "cpe" : "cpe:/o:redhat:rhel_aus:7.2",
    "package" : "kernel-0:3.10.0-327.96.1.el7"
  }, {
    "product_name" : "Red Hat Enterprise Linux 7.3 Advanced Update Support",
    "release_date" : "2021-04-27T00:00:00Z",
    "advisory" : "RHSA-2021:1373",
    "cpe" : "cpe:/o:redhat:rhel_aus:7.3",
    "package" : "kernel-0:3.10.0-514.88.1.el7"
  }, {
    "product_name" : "Red Hat Enterprise Linux 7.4 Advanced Update Support",
    "release_date" : "2021-04-20T00:00:00Z",
    "advisory" : "RHSA-2021:1267",
    "cpe" : "cpe:/o:redhat:rhel_aus:7.4",
    "package" : "kernel-0:3.10.0-693.84.1.el7"
  }, {
    "product_name" : "Red Hat Enterprise Linux 7.4 Telco Extended Update Support",
    "release_date" : "2021-04-20T00:00:00Z",
    "advisory" : "RHSA-2021:1267",
    "cpe" : "cpe:/o:redhat:rhel_tus:7.4",
    "package" : "kernel-0:3.10.0-693.84.1.el7"
  }, {
    "product_name" : "Red Hat Enterprise Linux 7.4 Update Services for SAP Solutions",
    "release_date" : "2021-04-20T00:00:00Z",
    "advisory" : "RHSA-2021:1267",
    "cpe" : "cpe:/o:redhat:rhel_e4s:7.4",
    "package" : "kernel-0:3.10.0-693.84.1.el7"
  }, {
    "product_name" : "Red Hat Enterprise Linux 7.6 Extended Update Support",
    "release_date" : "2021-04-27T00:00:00Z",
    "advisory" : "RHSA-2021:1376",
    "cpe" : "cpe:/o:redhat:rhel_eus:7.6",
    "package" : "kernel-0:3.10.0-957.72.1.el7"
  }, {
    "product_name" : "Red Hat Enterprise Linux 7.7 Extended Update Support",
    "release_date" : "2021-05-11T00:00:00Z",
    "advisory" : "RHSA-2021:1531",
    "cpe" : "cpe:/o:redhat:rhel_eus:7.7",
    "package" : "kernel-0:3.10.0-1062.49.1.el7"
  }, {
    "product_name" : "Red Hat Enterprise Linux 8",
    "release_date" : "2021-04-06T00:00:00Z",
    "advisory" : "RHSA-2021:1081",
    "cpe" : "cpe:/a:redhat:enterprise_linux:8::nfv",
    "package" : "kernel-rt-0:4.18.0-240.22.1.rt7.77.el8_3"
  }, {
    "product_name" : "Red Hat Enterprise Linux 8",
    "release_date" : "2021-04-06T00:00:00Z",
    "advisory" : "RHSA-2021:1093",
    "cpe" : "cpe:/o:redhat:enterprise_linux:8",
    "package" : "kernel-0:4.18.0-240.22.1.el8_3"
  }, {
    "product_name" : "Red Hat Enterprise Linux 8.1 Extended Update Support",
    "release_date" : "2021-04-13T00:00:00Z",
    "advisory" : "RHSA-2021:1171",
    "cpe" : "cpe:/o:redhat:rhel_eus:8.1",
    "package" : "kernel-0:4.18.0-147.44.1.el8_1"
  }, {
    "product_name" : "Red Hat Enterprise Linux 8.2 Extended Update Support",
    "release_date" : "2021-04-20T00:00:00Z",
    "advisory" : "RHSA-2021:1279",
    "cpe" : "cpe:/a:redhat:rhel_eus:8.2::nfv",
    "package" : "kernel-rt-0:4.18.0-193.51.1.rt13.101.el8_2"
  }, {
    "product_name" : "Red Hat Enterprise Linux 8.2 Extended Update Support",
    "release_date" : "2021-04-20T00:00:00Z",
    "advisory" : "RHSA-2021:1272",
    "cpe" : "cpe:/o:redhat:rhel_eus:8.2",
    "package" : "kernel-0:4.18.0-193.51.1.el8_2"
  }, {
    "product_name" : "Red Hat Virtualization 4.2 for Red Hat Enterprise Linux 7.6 EUS",
    "release_date" : "2021-04-27T00:00:00Z",
    "advisory" : "RHSA-2021:1376",
    "cpe" : "cpe:/o:redhat:enterprise_linux:7::hypervisor",
    "package" : "kernel-0:3.10.0-957.72.1.el7"
  } ],
  "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-alt",
    "cpe" : "cpe:/o:redhat:enterprise_linux:7"
  }, {
    "product_name" : "Red Hat Enterprise Linux 9",
    "fix_state" : "Not affected",
    "package_name" : "kernel",
    "cpe" : "cpe:/o:redhat:enterprise_linux:9"
  } ],
  "references" : [ "https://www.cve.org/CVERecord?id=CVE-2021-27363\nhttps://nvd.nist.gov/vuln/detail/CVE-2021-27363\nhttps://www.openwall.com/lists/oss-security/2021/03/06/1" ],
  "name" : "CVE-2021-27363",
  "mitigation" : {
    "value" : "The LIBISCSI module will be auto-loaded when required, its use can be disabled  by preventing the module from loading with the following instructions:\n# echo \"install libiscsi /bin/true\" >> /etc/modprobe.d/disable-libiscsi.conf\nThe system will need to be restarted if the libiscsi modules are loaded. In most circumstances, the libiscsi kernel modules will be unable to be unloaded while any network interfaces are active and the protocol is in use.\nIf the system requires iscsi to work correctly, this mitigation may not be suitable.\nIf you need further assistance, see KCS article https://access.redhat.com/solutions/41278 or contact Red Hat Global Support Services.",
    "lang" : "en:us"
  },
  "csaw" : false
}