{
  "threat_severity" : "Low",
  "public_date" : "2024-04-17T00:00:00Z",
  "bugzilla" : {
    "description" : "kernel: x86/mm: Disallow vsyscall page read for copy_from_kernel_nofault()",
    "id" : "2275635",
    "url" : "https://bugzilla.redhat.com/show_bug.cgi?id=2275635"
  },
  "cvss3" : {
    "cvss3_base_score" : "5.5",
    "cvss3_scoring_vector" : "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H",
    "status" : "verified"
  },
  "cwe" : "CWE-20",
  "details" : [ "In the Linux kernel, the following vulnerability has been resolved:\nx86/mm: Disallow vsyscall page read for copy_from_kernel_nofault()\nWhen trying to use copy_from_kernel_nofault() to read vsyscall page\nthrough a bpf program, the following oops was reported:\nBUG: unable to handle page fault for address: ffffffffff600000\n#PF: supervisor read access in kernel mode\n#PF: error_code(0x0000) - not-present page\nPGD 3231067 P4D 3231067 PUD 3233067 PMD 3235067 PTE 0\nOops: 0000 [#1] PREEMPT SMP PTI\nCPU: 1 PID: 20390 Comm: test_progs ...... 6.7.0+ #58\nHardware name: QEMU Standard PC (i440FX + PIIX, 1996) ......\nRIP: 0010:copy_from_kernel_nofault+0x6f/0x110\n......\nCall Trace:\n<TASK>\n? copy_from_kernel_nofault+0x6f/0x110\nbpf_probe_read_kernel+0x1d/0x50\nbpf_prog_2061065e56845f08_do_probe_read+0x51/0x8d\ntrace_call_bpf+0xc5/0x1c0\nperf_call_bpf_enter.isra.0+0x69/0xb0\nperf_syscall_enter+0x13e/0x200\nsyscall_trace_enter+0x188/0x1c0\ndo_syscall_64+0xb5/0xe0\nentry_SYSCALL_64_after_hwframe+0x6e/0x76\n</TASK>\n......\n---[ end trace 0000000000000000 ]---\nThe oops is triggered when:\n1) A bpf program uses bpf_probe_read_kernel() to read from the vsyscall\npage and invokes copy_from_kernel_nofault() which in turn calls\n__get_user_asm().\n2) Because the vsyscall page address is not readable from kernel space,\na page fault exception is triggered accordingly.\n3) handle_page_fault() considers the vsyscall page address as a user\nspace address instead of a kernel space address. This results in the\nfix-up setup by bpf not being applied and a page_fault_oops() is invoked\ndue to SMAP.\nConsidering handle_page_fault() has already considered the vsyscall page\naddress as a userspace address, fix the problem by disallowing vsyscall\npage read for copy_from_kernel_nofault().", "In the Linux kernel, the following vulnerability has been resolved:\nx86/mm: Disallow vsyscall page read for copy_from_kernel_nofault()\nThe Linux kernel CVE team has assigned CVE-2024-26906 to this issue.\nUpstream advisory:\nhttps://lore.kernel.org/linux-cve-announce/2024041746-CVE-2024-26906-bb35@gregkh/T" ],
  "affected_release" : [ {
    "product_name" : "Red Hat Enterprise Linux 8",
    "release_date" : "2024-07-08T00:00:00Z",
    "advisory" : "RHSA-2024:4352",
    "cpe" : "cpe:/a:redhat:enterprise_linux:8::nfv",
    "package" : "kernel-rt-0:4.18.0-553.8.1.rt7.349.el8_10"
  }, {
    "product_name" : "Red Hat Enterprise Linux 8",
    "release_date" : "2024-07-02T00:00:00Z",
    "advisory" : "RHSA-2024:4211",
    "cpe" : "cpe:/o:redhat:enterprise_linux:8",
    "package" : "kernel-0:4.18.0-553.8.1.el8_10"
  }, {
    "product_name" : "Red Hat Enterprise Linux 9",
    "release_date" : "2024-11-12T00:00:00Z",
    "advisory" : "RHSA-2024:9315",
    "cpe" : "cpe:/a:redhat:enterprise_linux:9",
    "package" : "kernel-0:5.14.0-503.11.1.el9_5"
  }, {
    "product_name" : "Red Hat Enterprise Linux 9",
    "release_date" : "2024-11-12T00:00:00Z",
    "advisory" : "RHSA-2024:9315",
    "cpe" : "cpe:/o:redhat:enterprise_linux:9",
    "package" : "kernel-0:5.14.0-503.11.1.el9_5"
  }, {
    "product_name" : "Red Hat Enterprise Linux 9.2 Extended Update Support",
    "release_date" : "2024-11-13T00:00:00Z",
    "advisory" : "RHSA-2024:9497",
    "cpe" : "cpe:/a:redhat:rhel_eus:9.2",
    "package" : "kernel-0:5.14.0-284.92.1.el9_2"
  }, {
    "product_name" : "Red Hat Enterprise Linux 9.2 Extended Update Support",
    "release_date" : "2024-11-13T00:00:00Z",
    "advisory" : "RHSA-2024:9498",
    "cpe" : "cpe:/a:redhat:rhel_eus:9.2::nfv",
    "package" : "kernel-rt-0:5.14.0-284.92.1.rt14.377.el9_2"
  }, {
    "product_name" : "Red Hat Enterprise Linux 9.4 Extended Update Support",
    "release_date" : "2024-11-13T00:00:00Z",
    "advisory" : "RHSA-2024:9546",
    "cpe" : "cpe:/a:redhat:rhel_eus:9.4",
    "package" : "kernel-0:5.14.0-427.44.1.el9_4"
  } ],
  "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-2024-26906\nhttps://nvd.nist.gov/vuln/detail/CVE-2024-26906\nhttps://lore.kernel.org/linux-cve-announce/2024041746-CVE-2024-26906-bb35@gregkh/T" ],
  "name" : "CVE-2024-26906",
  "csaw" : false
}