Amazon Linux 2 : kernel (ALASKERNEL-5.10-2022-006) - Nessus

High   Plugin ID: 160432

This page contains detailed information about the Amazon Linux 2 : kernel (ALASKERNEL-5.10-2022-006) Nessus plugin including available exploits and PoCs found on GitHub, in Metasploit or Exploit-DB for verifying of this vulnerability.

Plugin Overview


ID: 160432
Name: Amazon Linux 2 : kernel (ALASKERNEL-5.10-2022-006)
Filename: al2_ALASKERNEL-5_10-2022-006.nasl
Vulnerability Published: 2020-10-15
This Plugin Published: 2022-05-02
Last Modification Time: 2022-05-02
Plugin Version: 1.2
Plugin Type: local
Plugin Family: Amazon Linux Local Security Checks
Dependencies: ssh_get_info.nasl
Required KB Items [?]: Host/AmazonLinux/release, Host/AmazonLinux/rpm-list, Host/local_checks_enabled

Vulnerability Information


Severity: High
Vulnerability Published: 2020-10-15
Patch Published: 2022-01-20
CVE [?]: CVE-2020-16119, CVE-2021-20322, CVE-2021-41073
CPE [?]: cpe:/o:amazon:linux:2, p-cpe:/a:amazon:linux:bpftool, p-cpe:/a:amazon:linux:bpftool-debuginfo, p-cpe:/a:amazon:linux:kernel, p-cpe:/a:amazon:linux:kernel-debuginfo, p-cpe:/a:amazon:linux:kernel-debuginfo-common-aarch64, p-cpe:/a:amazon:linux:kernel-debuginfo-common-x86_64, p-cpe:/a:amazon:linux:kernel-devel, p-cpe:/a:amazon:linux:kernel-headers, p-cpe:/a:amazon:linux:kernel-livepatch-5.10.68-62.173, p-cpe:/a:amazon:linux:kernel-tools, p-cpe:/a:amazon:linux:kernel-tools-debuginfo, p-cpe:/a:amazon:linux:kernel-tools-devel, p-cpe:/a:amazon:linux:perf, p-cpe:/a:amazon:linux:perf-debuginfo, p-cpe:/a:amazon:linux:python-perf, p-cpe:/a:amazon:linux:python-perf-debuginfo

Synopsis

The remote Amazon Linux 2 host is missing a security update.

Description

The version of kernel installed on the remote host is prior to 5.10.68-62.173. It is, therefore, affected by multiple vulnerabilities as referenced in the ALAS2KERNEL-5.10-2022-006 advisory.

- Use-after-free vulnerability in the Linux kernel exploitable by a local attacker due to reuse of a DCCP socket with an attached dccps_hc_tx_ccid object as a listener after being released. Fixed in Ubuntu Linux kernel 5.4.0-51.56, 5.3.0-68.63, 4.15.0-121.123, 4.4.0-193.224, 3.13.0.182.191 and 3.2.0-149.196. (CVE-2020-16119)

- A flaw in the processing of received ICMP errors (ICMP fragment needed and ICMP redirect) in the Linux kernel functionality was found to allow the ability to quickly scan open UDP ports. This flaw allows an off-path remote user to effectively bypass the source port UDP randomization. The highest threat from this vulnerability is to confidentiality and possibly integrity, because software that relies on UDP source port randomization are indirectly affected as well. (CVE-2021-20322)

- loop_rw_iter in fs/io_uring.c in the Linux kernel 5.10 through 5.14.6 allows local users to gain privileges by using IORING_OP_PROVIDE_BUFFERS to trigger a free of a kernel buffer, as demonstrated by using /proc/<pid>/maps for exploitation. (CVE-2021-41073)

Note that Nessus has not tested for these issues but has instead relied only on the application's self-reported version number.

Solution

Run 'yum update kernel' to update your system.

Public Exploits


Target Network Port(s): N/A
Target Asset(s): N/A
Exploit Available: True (GitHub)
Exploit Ease: Exploits (PoCs) are available

Here's the list of publicly known exploits and PoCs for verifying the Amazon Linux 2 : kernel (ALASKERNEL-5.10-2022-006) vulnerability:

  1. GitHub: https://github.com/HadarManor/Public-Vulnerabilities
    [CVE-2020-16119]
  2. GitHub: https://github.com/xairy/linux-kernel-exploitation
    [CVE-2020-16119]
  3. GitHub: https://github.com/AlAIAL90/CVE-2021-41073
    [CVE-2021-41073: PoC for exploiting CVE-2021-41073 : loop_rw_iter in fs/io_uring.c in the Linux ...]
  4. GitHub: https://github.com/chompie1337/Linux_LPE_io_uring_CVE-2021-41073
    [CVE-2021-41073]

Before running any exploit against any system, make sure you are authorized by the owner of the target system(s) to perform such activity. In any other case, this would be considered as an illegal activity.

WARNING: Beware of using unverified exploits from sources such as GitHub or Exploit-DB. These exploits and PoCs could contain malware. For more information, see how to use exploits safely.

Risk Information


CVSS Score Source [?]: CVE-2021-41073
CVSS V2 Vector: AV:L/AC:L/Au:N/C:C/I:C/A:C/E:U/RL:OF/RC:C
CVSS Base Score:7.2 (High)
Impact Subscore:10.0
Exploitability Subscore:3.9
CVSS Temporal Score:5.3 (Medium)
CVSS Environmental Score:NA (None)
Modified Impact Subscore:NA
Overall CVSS Score:5.3 (Medium)
CVSS V3 Vector: CVSS:3.0/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H/E:U/RL:O/RC:C
CVSS Base Score:7.8 (High)
Impact Subscore:5.9
Exploitability Subscore:1.8
CVSS Temporal Score:6.8 (Medium)
CVSS Environmental Score:NA (None)
Modified Impact Subscore:NA
Overall CVSS Score:6.8 (Medium)

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Plugin Source


This is the al2_ALASKERNEL-5_10-2022-006.nasl nessus plugin source code. This script is Copyright (C) 2022 and is owned by Tenable, Inc. or an Affiliate thereof.

##
# (C) Tenable, Inc.
#
# The descriptive text and package checks in this plugin were
# extracted from Amazon Linux 2 Security Advisory ALASKERNEL-5.10-2022-006.
##

include('compat.inc');

if (description)
{
  script_id(160432);
  script_version("1.2");
  script_set_attribute(attribute:"plugin_modification_date", value:"2022/05/02");

  script_cve_id("CVE-2020-16119", "CVE-2021-20322", "CVE-2021-41073");

  script_name(english:"Amazon Linux 2 : kernel (ALASKERNEL-5.10-2022-006)");

  script_set_attribute(attribute:"synopsis", value:
"The remote Amazon Linux 2 host is missing a security update.");
  script_set_attribute(attribute:"description", value:
"The version of kernel installed on the remote host is prior to 5.10.68-62.173. It is, therefore, affected by multiple
vulnerabilities as referenced in the ALAS2KERNEL-5.10-2022-006 advisory.

  - Use-after-free vulnerability in the Linux kernel exploitable by a local attacker due to reuse of a DCCP
    socket with an attached dccps_hc_tx_ccid object as a listener after being released. Fixed in Ubuntu Linux
    kernel 5.4.0-51.56, 5.3.0-68.63, 4.15.0-121.123, 4.4.0-193.224, 3.13.0.182.191 and 3.2.0-149.196.
    (CVE-2020-16119)

  - A flaw in the processing of received ICMP errors (ICMP fragment needed and ICMP redirect) in the Linux
    kernel functionality was found to allow the ability to quickly scan open UDP ports. This flaw allows an
    off-path remote user to effectively bypass the source port UDP randomization. The highest threat from this
    vulnerability is to confidentiality and possibly integrity, because software that relies on UDP source
    port randomization are indirectly affected as well. (CVE-2021-20322)

  - loop_rw_iter in fs/io_uring.c in the Linux kernel 5.10 through 5.14.6 allows local users to gain
    privileges by using IORING_OP_PROVIDE_BUFFERS to trigger a free of a kernel buffer, as demonstrated by
    using /proc/<pid>/maps for exploitation. (CVE-2021-41073)

Note that Nessus has not tested for these issues but has instead relied only on the application's self-reported version
number.");
  script_set_attribute(attribute:"see_also", value:"https://alas.aws.amazon.com/AL2/ALASKERNEL-5.10-2022-006.html");
  script_set_attribute(attribute:"see_also", value:"https://alas.aws.amazon.com/cve/html/CVE-2020-16119.html");
  script_set_attribute(attribute:"see_also", value:"https://alas.aws.amazon.com/cve/html/CVE-2021-20322.html");
  script_set_attribute(attribute:"see_also", value:"https://alas.aws.amazon.com/cve/html/CVE-2021-41073.html");
  script_set_attribute(attribute:"solution", value:
"Run 'yum update kernel' to update your system.");
  script_set_cvss_base_vector("CVSS2#AV:L/AC:L/Au:N/C:C/I:C/A:C");
  script_set_cvss_temporal_vector("CVSS2#E:U/RL:OF/RC:C");
  script_set_cvss3_base_vector("CVSS:3.0/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H");
  script_set_cvss3_temporal_vector("CVSS:3.0/E:U/RL:O/RC:C");
  script_set_attribute(attribute:"cvss_score_source", value:"CVE-2021-41073");

  script_set_attribute(attribute:"exploitability_ease", value:"No known exploits are available");
  script_set_attribute(attribute:"exploit_available", value:"false");

  script_set_attribute(attribute:"vuln_publication_date", value:"2020/10/15");
  script_set_attribute(attribute:"patch_publication_date", value:"2022/01/20");
  script_set_attribute(attribute:"plugin_publication_date", value:"2022/05/02");

  script_set_attribute(attribute:"plugin_type", value:"local");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:amazon:linux:bpftool");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:amazon:linux:bpftool-debuginfo");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:amazon:linux:kernel");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:amazon:linux:kernel-debuginfo");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:amazon:linux:kernel-debuginfo-common-aarch64");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:amazon:linux:kernel-debuginfo-common-x86_64");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:amazon:linux:kernel-devel");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:amazon:linux:kernel-headers");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:amazon:linux:kernel-livepatch-5.10.68-62.173");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:amazon:linux:kernel-tools");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:amazon:linux:kernel-tools-debuginfo");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:amazon:linux:kernel-tools-devel");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:amazon:linux:perf");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:amazon:linux:perf-debuginfo");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:amazon:linux:python-perf");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:amazon:linux:python-perf-debuginfo");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:amazon:linux:2");
  script_end_attributes();

  script_category(ACT_GATHER_INFO);
  script_family(english:"Amazon Linux Local Security Checks");

  script_copyright(english:"This script is Copyright (C) 2022 and is owned by Tenable, Inc. or an Affiliate thereof.");

  script_dependencies("ssh_get_info.nasl");
  script_require_keys("Host/local_checks_enabled", "Host/AmazonLinux/release", "Host/AmazonLinux/rpm-list");

  exit(0);
}

include("rpm.inc");
include("hotfixes.inc");

if (!get_kb_item("Host/local_checks_enabled")) audit(AUDIT_LOCAL_CHECKS_NOT_ENABLED);

var release = get_kb_item("Host/AmazonLinux/release");
if (isnull(release) || !strlen(release)) audit(AUDIT_OS_NOT, "Amazon Linux");
var os_ver = pregmatch(pattern: "^AL(A|\d)", string:release);
if (isnull(os_ver)) audit(AUDIT_UNKNOWN_APP_VER, "Amazon Linux");
var os_ver = os_ver[1];
if (os_ver != "2")
{
  if (os_ver == 'A') os_ver = 'AMI';
  audit(AUDIT_OS_NOT, "Amazon Linux 2", "Amazon Linux " + os_ver);
}

if (!get_kb_item("Host/AmazonLinux/rpm-list")) audit(AUDIT_PACKAGE_LIST_MISSING);

if (get_one_kb_item("Host/kpatch/kernel-cves"))
{
  set_hotfix_type("kpatch");
  var cve_list = make_list("CVE-2020-16119", "CVE-2021-20322", "CVE-2021-41073");
  if (hotfix_cves_check(cve_list))
  {
    audit(AUDIT_PATCH_INSTALLED, "kpatch hotfix for ALASKERNEL-5.10-2022-006");
  }
  else
  {
    __rpm_report = hotfix_reporting_text();
  }
}
var pkgs = [
    {'reference':'bpftool-5.10.68-62.173.amzn2', 'cpu':'aarch64', 'release':'AL2', 'rpm_spec_vers_cmp':TRUE},
    {'reference':'bpftool-5.10.68-62.173.amzn2', 'cpu':'x86_64', 'release':'AL2', 'rpm_spec_vers_cmp':TRUE},
    {'reference':'bpftool-debuginfo-5.10.68-62.173.amzn2', 'cpu':'aarch64', 'release':'AL2', 'rpm_spec_vers_cmp':TRUE},
    {'reference':'bpftool-debuginfo-5.10.68-62.173.amzn2', 'cpu':'x86_64', 'release':'AL2', 'rpm_spec_vers_cmp':TRUE},
    {'reference':'kernel-5.10.68-62.173.amzn2', 'cpu':'aarch64', 'release':'AL2', 'rpm_spec_vers_cmp':TRUE},
    {'reference':'kernel-5.10.68-62.173.amzn2', 'cpu':'x86_64', 'release':'AL2', 'rpm_spec_vers_cmp':TRUE},
    {'reference':'kernel-debuginfo-5.10.68-62.173.amzn2', 'cpu':'aarch64', 'release':'AL2', 'rpm_spec_vers_cmp':TRUE},
    {'reference':'kernel-debuginfo-5.10.68-62.173.amzn2', 'cpu':'x86_64', 'release':'AL2', 'rpm_spec_vers_cmp':TRUE},
    {'reference':'kernel-debuginfo-common-aarch64-5.10.68-62.173.amzn2', 'cpu':'aarch64', 'release':'AL2', 'rpm_spec_vers_cmp':TRUE},
    {'reference':'kernel-debuginfo-common-x86_64-5.10.68-62.173.amzn2', 'cpu':'x86_64', 'release':'AL2', 'rpm_spec_vers_cmp':TRUE},
    {'reference':'kernel-devel-5.10.68-62.173.amzn2', 'cpu':'aarch64', 'release':'AL2', 'rpm_spec_vers_cmp':TRUE},
    {'reference':'kernel-devel-5.10.68-62.173.amzn2', 'cpu':'x86_64', 'release':'AL2', 'rpm_spec_vers_cmp':TRUE},
    {'reference':'kernel-headers-5.10.68-62.173.amzn2', 'cpu':'aarch64', 'release':'AL2', 'rpm_spec_vers_cmp':TRUE},
    {'reference':'kernel-headers-5.10.68-62.173.amzn2', 'cpu':'i686', 'release':'AL2', 'rpm_spec_vers_cmp':TRUE},
    {'reference':'kernel-headers-5.10.68-62.173.amzn2', 'cpu':'x86_64', 'release':'AL2', 'rpm_spec_vers_cmp':TRUE},
    {'reference':'kernel-livepatch-5.10.68-62.173-1.0-0.amzn2', 'cpu':'x86_64', 'release':'AL2', 'rpm_spec_vers_cmp':TRUE},
    {'reference':'kernel-tools-5.10.68-62.173.amzn2', 'cpu':'aarch64', 'release':'AL2', 'rpm_spec_vers_cmp':TRUE},
    {'reference':'kernel-tools-5.10.68-62.173.amzn2', 'cpu':'x86_64', 'release':'AL2', 'rpm_spec_vers_cmp':TRUE},
    {'reference':'kernel-tools-debuginfo-5.10.68-62.173.amzn2', 'cpu':'aarch64', 'release':'AL2', 'rpm_spec_vers_cmp':TRUE},
    {'reference':'kernel-tools-debuginfo-5.10.68-62.173.amzn2', 'cpu':'x86_64', 'release':'AL2', 'rpm_spec_vers_cmp':TRUE},
    {'reference':'kernel-tools-devel-5.10.68-62.173.amzn2', 'cpu':'aarch64', 'release':'AL2', 'rpm_spec_vers_cmp':TRUE},
    {'reference':'kernel-tools-devel-5.10.68-62.173.amzn2', 'cpu':'x86_64', 'release':'AL2', 'rpm_spec_vers_cmp':TRUE},
    {'reference':'perf-5.10.68-62.173.amzn2', 'cpu':'aarch64', 'release':'AL2', 'rpm_spec_vers_cmp':TRUE},
    {'reference':'perf-5.10.68-62.173.amzn2', 'cpu':'x86_64', 'release':'AL2', 'rpm_spec_vers_cmp':TRUE},
    {'reference':'perf-debuginfo-5.10.68-62.173.amzn2', 'cpu':'aarch64', 'release':'AL2', 'rpm_spec_vers_cmp':TRUE},
    {'reference':'perf-debuginfo-5.10.68-62.173.amzn2', 'cpu':'x86_64', 'release':'AL2', 'rpm_spec_vers_cmp':TRUE},
    {'reference':'python-perf-5.10.68-62.173.amzn2', 'cpu':'aarch64', 'release':'AL2', 'rpm_spec_vers_cmp':TRUE},
    {'reference':'python-perf-5.10.68-62.173.amzn2', 'cpu':'x86_64', 'release':'AL2', 'rpm_spec_vers_cmp':TRUE},
    {'reference':'python-perf-debuginfo-5.10.68-62.173.amzn2', 'cpu':'aarch64', 'release':'AL2', 'rpm_spec_vers_cmp':TRUE},
    {'reference':'python-perf-debuginfo-5.10.68-62.173.amzn2', 'cpu':'x86_64', 'release':'AL2', 'rpm_spec_vers_cmp':TRUE}
];

var flag = 0;
foreach package_array ( pkgs ) {
  var reference = NULL;
  var release = NULL;
  var cpu = NULL;
  var el_string = NULL;
  var rpm_spec_vers_cmp = NULL;
  var allowmaj = NULL;
  if (!empty_or_null(package_array['reference'])) reference = package_array['reference'];
  if (!empty_or_null(package_array['release'])) release = package_array['release'];
  if (!empty_or_null(package_array['cpu'])) cpu = package_array['cpu'];
  if (!empty_or_null(package_array['el_string'])) el_string = package_array['el_string'];
  if (!empty_or_null(package_array['rpm_spec_vers_cmp'])) rpm_spec_vers_cmp = package_array['rpm_spec_vers_cmp'];
  if (!empty_or_null(package_array['allowmaj'])) allowmaj = package_array['allowmaj'];
  if (reference && release) {
    if (rpm_check(release:release, cpu:cpu, reference:reference, el_string:el_string, rpm_spec_vers_cmp:rpm_spec_vers_cmp, allowmaj:allowmaj)) flag++;
  }
}

if (flag)
{
  security_report_v4(
      port       : 0,
      severity   : SECURITY_HOLE,
      extra      : rpm_report_get()
  );
  exit(0);
}
else
{
  var tested = pkg_tests_get();
  if (tested) audit(AUDIT_PACKAGE_NOT_AFFECTED, tested);
  else audit(AUDIT_PACKAGE_NOT_INSTALLED, "bpftool / bpftool-debuginfo / kernel / etc");
}

The latest version of this script can be found in these locations depending on your platform:

  • Linux / Unix:
    /opt/nessus/lib/nessus/plugins/al2_ALASKERNEL-5_10-2022-006.nasl
  • Windows:
    C:\ProgramData\Tenable\Nessus\nessus\plugins\al2_ALASKERNEL-5_10-2022-006.nasl
  • Mac OS X:
    /Library/Nessus/run/lib/nessus/plugins/al2_ALASKERNEL-5_10-2022-006.nasl

Go back to menu.

How to Run


Here is how to run the Amazon Linux 2 : kernel (ALASKERNEL-5.10-2022-006) as a standalone plugin via the Nessus web user interface (https://localhost:8834/):

  1. Click to start a New Scan.
  2. Select Advanced Scan.
  3. Navigate to the Plugins tab.
  4. On the top right corner click to Disable All plugins.
  5. On the left side table select Amazon Linux Local Security Checks plugin family.
  6. On the right side table select Amazon Linux 2 : kernel (ALASKERNEL-5.10-2022-006) plugin ID 160432.
  7. Specify the target on the Settings tab and click to Save the scan.
  8. Run the scan.

Here are a few examples of how to run the plugin in the command line. Note that the examples below demonstrate the usage on the Linux / Unix platform.

Basic usage:

/opt/nessus/bin/nasl al2_ALASKERNEL-5_10-2022-006.nasl -t <IP/HOST>

Run the plugin with audit trail message on the console:

/opt/nessus/bin/nasl -a al2_ALASKERNEL-5_10-2022-006.nasl -t <IP/HOST>

Run the plugin with trace script execution written to the console (useful for debugging):

/opt/nessus/bin/nasl -T - al2_ALASKERNEL-5_10-2022-006.nasl -t <IP/HOST>

Run the plugin with using a state file for the target and updating it (useful for running multiple plugins on the target):

/opt/nessus/bin/nasl -K /tmp/state al2_ALASKERNEL-5_10-2022-006.nasl -t <IP/HOST>

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References


See also: Similar and related Nessus plugins:
  • 155930 - SUSE SLES15 Security Update : kernel (SUSE-SU-2021:3969-1)
  • 155959 - SUSE SLES12 Security Update : kernel (SUSE-SU-2021:3972-1)
  • 155981 - SUSE SLES15 Security Update : the Linux RT Kernel (SUSE-SU-2021:3978-1)
  • 155992 - SUSE SLES15 Security Update : the Linux RT Kernel (SUSE-SU-2021:3979-1)
  • 156009 - SUSE SLES12 Security Update : the Linux RT Kernel (SUSE-SU-2021:3992-1)
  • 156163 - Debian DLA-2843-1 : linux - LTS security update
  • 156431 - EulerOS 2.0 SP5 : kernel (EulerOS-SA-2021-2934)
  • 157208 - EulerOS 2.0 SP9 : kernel (EulerOS-SA-2022-1010)
  • 157213 - EulerOS 2.0 SP9 : kernel (EulerOS-SA-2022-1030)
  • 157352 - Ubuntu 16.04 LTS / 18.04 LTS : Linux kernel vulnerabilities (USN-5268-1)
  • 157410 - Amazon Linux AMI : kernel (ALAS-2022-1563)
  • 158288 - EulerOS 2.0 SP3 : kernel (EulerOS-SA-2022-1171)
  • 158396 - EulerOS 2.0 SP10 : kernel (EulerOS-SA-2022-1208)
  • 158416 - EulerOS 2.0 SP10 : kernel (EulerOS-SA-2022-1243)
  • 158761 - Debian DSA-5096-1 : linux - security update
  • 159840 - EulerOS Virtualization 2.10.1 : kernel (EulerOS-SA-2022-1376)
  • 159861 - EulerOS Virtualization 2.10.0 : kernel (EulerOS-SA-2022-1402)
  • 160449 - Amazon Linux 2 : kernel (ALASKERNEL-5.4-2022-008)

Version


This page has been produced using Nessus Professional 10.1.2 (#68) LINUX, Plugin set 202205072148.
Plugin file al2_ALASKERNEL-5_10-2022-006.nasl version 1.2. For more plugins, visit the Nessus Plugin Library.

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