The version of kernel installed on the remote host is prior to 4.14.262-135.489. It is, therefore, affected by multiple vulnerabilities as referenced in the ALAS-2022-1563 advisory.
Rogue backends can cause DoS of guests via high frequency events T[his CNA information record relates to multiple CVEs; the text explains which aspects/vulnerabilities correspond to which CVE.] Xen offers the ability to run PV backends in regular unprivileged guests, typically referred to as driver domains.
Running PV backends in driver domains has one primary security advantage: if a driver domain gets compromised, it doesn’t have the privileges to take over the system. However, a malicious driver domain could try to attack other guests via sending events at a high frequency leading to a Denial of Service in the guest due to trying to service interrupts for elongated amounts of time. There are three affected backends: * blkfront patch 1, CVE-2021-28711 * netfront patch 2, CVE-2021-28712 * hvc_xen (console) patch 3, CVE-2021-28713 (CVE-2021-28711, CVE-2021-28712, CVE-2021-28713)
Guest can force Linux netback driver to hog large amounts of kernel memory T[his CNA information record relates to multiple CVEs; the text explains which aspects/vulnerabilities correspond to which CVE.] Incoming data packets for a guest in the Linux kernel’s netback driver are buffered until the guest is ready to process them. There are some measures taken for avoiding to pile up too much data, but those can be bypassed by the guest: There is a timeout how long the client side of an interface can stop consuming new packets before it is assumed to have stalled, but this timeout is rather long (60 seconds by default).
Using a UDP connection on a fast interface can easily accumulate gigabytes of data in that time.
(CVE-2021-28715) The timeout could even never trigger if the guest manages to have only one free slot in its RX queue ring page and the next package would require more than one free slot, which may be the case when using GSO, XDP, or software hashing. (CVE-2021-28714) (CVE-2021-28714, CVE-2021-28715)
Note that Nessus has not tested for this issue but has instead relied only on the application’s self-reported version number.
#%NASL_MIN_LEVEL 70300
##
# (C) Tenable Network Security, Inc.
#
# The descriptive text and package checks in this plugin were
# extracted from Amazon Linux AMI Security Advisory ALAS-2022-1563.
##
include('deprecated_nasl_level.inc');
include('compat.inc');
if (description)
{
script_id(157410);
script_version("1.9");
script_set_attribute(attribute:"plugin_modification_date", value:"2023/12/07");
script_cve_id(
"CVE-2021-3772",
"CVE-2021-4002",
"CVE-2021-4155",
"CVE-2021-20322",
"CVE-2021-28711",
"CVE-2021-28712",
"CVE-2021-28713",
"CVE-2021-28714",
"CVE-2021-28715",
"CVE-2022-0492"
);
script_xref(name:"ALAS", value:"2022-1563");
script_name(english:"Amazon Linux AMI : kernel (ALAS-2022-1563)");
script_set_attribute(attribute:"synopsis", value:
"The remote Amazon Linux AMI host is missing a security update.");
script_set_attribute(attribute:"description", value:
"The version of kernel installed on the remote host is prior to 4.14.262-135.489. It is, therefore, affected by multiple
vulnerabilities as referenced in the ALAS-2022-1563 advisory.
- Rogue backends can cause DoS of guests via high frequency events T[his CNA information record relates to
multiple CVEs; the text explains which aspects/vulnerabilities correspond to which CVE.] Xen offers the
ability to run PV backends in regular unprivileged guests, typically referred to as driver domains.
Running PV backends in driver domains has one primary security advantage: if a driver domain gets
compromised, it doesn't have the privileges to take over the system. However, a malicious driver domain
could try to attack other guests via sending events at a high frequency leading to a Denial of Service in
the guest due to trying to service interrupts for elongated amounts of time. There are three affected
backends: * blkfront patch 1, CVE-2021-28711 * netfront patch 2, CVE-2021-28712 * hvc_xen (console) patch
3, CVE-2021-28713 (CVE-2021-28711, CVE-2021-28712, CVE-2021-28713)
- Guest can force Linux netback driver to hog large amounts of kernel memory T[his CNA information record
relates to multiple CVEs; the text explains which aspects/vulnerabilities correspond to which CVE.]
Incoming data packets for a guest in the Linux kernel's netback driver are buffered until the guest is
ready to process them. There are some measures taken for avoiding to pile up too much data, but those can
be bypassed by the guest: There is a timeout how long the client side of an interface can stop consuming
new packets before it is assumed to have stalled, but this timeout is rather long (60 seconds by default).
Using a UDP connection on a fast interface can easily accumulate gigabytes of data in that time.
(CVE-2021-28715) The timeout could even never trigger if the guest manages to have only one free slot in
its RX queue ring page and the next package would require more than one free slot, which may be the case
when using GSO, XDP, or software hashing. (CVE-2021-28714) (CVE-2021-28714, CVE-2021-28715)
Note that Nessus has not tested for this issue 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/ALAS-2022-1563.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-2021-28711.html");
script_set_attribute(attribute:"see_also", value:"https://alas.aws.amazon.com/cve/html/CVE-2021-28712.html");
script_set_attribute(attribute:"see_also", value:"https://alas.aws.amazon.com/cve/html/CVE-2021-28713.html");
script_set_attribute(attribute:"see_also", value:"https://alas.aws.amazon.com/cve/html/CVE-2021-28714.html");
script_set_attribute(attribute:"see_also", value:"https://alas.aws.amazon.com/cve/html/CVE-2021-28715.html");
script_set_attribute(attribute:"see_also", value:"https://alas.aws.amazon.com/cve/html/CVE-2021-3772.html");
script_set_attribute(attribute:"see_also", value:"https://alas.aws.amazon.com/cve/html/CVE-2021-4002.html");
script_set_attribute(attribute:"see_also", value:"https://alas.aws.amazon.com/cve/html/CVE-2021-4155.html");
script_set_attribute(attribute:"see_also", value:"https://alas.aws.amazon.com/cve/html/CVE-2022-0492.html");
script_set_attribute(attribute:"solution", value:
"Run 'yum update kernel' to update your system.");
script_set_cvss_base_vector("CVSS2#AV:L/AC:M/Au:N/C:C/I:C/A:C");
script_set_cvss_temporal_vector("CVSS2#E:F/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:F/RL:O/RC:C");
script_set_attribute(attribute:"cvss_score_source", value:"CVE-2022-0492");
script_set_attribute(attribute:"exploitability_ease", value:"Exploits are available");
script_set_attribute(attribute:"exploit_available", value:"true");
script_set_attribute(attribute:"metasploit_name", value:'Docker cgroups Container Escape');
script_set_attribute(attribute:"exploit_framework_metasploit", value:"true");
script_set_attribute(attribute:"vuln_publication_date", value:"2021/01/11");
script_set_attribute(attribute:"patch_publication_date", value:"2022/02/04");
script_set_attribute(attribute:"plugin_publication_date", value:"2022/02/07");
script_set_attribute(attribute:"plugin_type", value:"local");
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-i686");
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-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:"cpe:/o:amazon:linux");
script_end_attributes();
script_category(ACT_GATHER_INFO);
script_family(english:"Amazon Linux Local Security Checks");
script_copyright(english:"This script is Copyright (C) 2022-2023 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("audit.inc");
include("global_settings.inc");
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 != "A")
{
if (os_ver == 'A') os_ver = 'AMI';
audit(AUDIT_OS_NOT, "Amazon Linux AMI", "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-2021-3772", "CVE-2021-4002", "CVE-2021-4155", "CVE-2021-20322", "CVE-2021-28711", "CVE-2021-28712", "CVE-2021-28713", "CVE-2021-28714", "CVE-2021-28715", "CVE-2022-0492");
if (hotfix_cves_check(cve_list))
{
audit(AUDIT_PATCH_INSTALLED, "kpatch hotfix for ALAS-2022-1563");
}
else
{
__rpm_report = hotfix_reporting_text();
}
}
var pkgs = [
{'reference':'kernel-4.14.262-135.489.amzn1', 'cpu':'i686', 'release':'ALA', 'rpm_spec_vers_cmp':TRUE},
{'reference':'kernel-4.14.262-135.489.amzn1', 'cpu':'x86_64', 'release':'ALA', 'rpm_spec_vers_cmp':TRUE},
{'reference':'kernel-debuginfo-4.14.262-135.489.amzn1', 'cpu':'i686', 'release':'ALA', 'rpm_spec_vers_cmp':TRUE},
{'reference':'kernel-debuginfo-4.14.262-135.489.amzn1', 'cpu':'x86_64', 'release':'ALA', 'rpm_spec_vers_cmp':TRUE},
{'reference':'kernel-debuginfo-common-i686-4.14.262-135.489.amzn1', 'cpu':'i686', 'release':'ALA', 'rpm_spec_vers_cmp':TRUE},
{'reference':'kernel-debuginfo-common-x86_64-4.14.262-135.489.amzn1', 'cpu':'x86_64', 'release':'ALA', 'rpm_spec_vers_cmp':TRUE},
{'reference':'kernel-devel-4.14.262-135.489.amzn1', 'cpu':'i686', 'release':'ALA', 'rpm_spec_vers_cmp':TRUE},
{'reference':'kernel-devel-4.14.262-135.489.amzn1', 'cpu':'x86_64', 'release':'ALA', 'rpm_spec_vers_cmp':TRUE},
{'reference':'kernel-headers-4.14.262-135.489.amzn1', 'cpu':'i686', 'release':'ALA', 'rpm_spec_vers_cmp':TRUE},
{'reference':'kernel-headers-4.14.262-135.489.amzn1', 'cpu':'x86_64', 'release':'ALA', 'rpm_spec_vers_cmp':TRUE},
{'reference':'kernel-tools-4.14.262-135.489.amzn1', 'cpu':'i686', 'release':'ALA', 'rpm_spec_vers_cmp':TRUE},
{'reference':'kernel-tools-4.14.262-135.489.amzn1', 'cpu':'x86_64', 'release':'ALA', 'rpm_spec_vers_cmp':TRUE},
{'reference':'kernel-tools-debuginfo-4.14.262-135.489.amzn1', 'cpu':'i686', 'release':'ALA', 'rpm_spec_vers_cmp':TRUE},
{'reference':'kernel-tools-debuginfo-4.14.262-135.489.amzn1', 'cpu':'x86_64', 'release':'ALA', 'rpm_spec_vers_cmp':TRUE},
{'reference':'kernel-tools-devel-4.14.262-135.489.amzn1', 'cpu':'i686', 'release':'ALA', 'rpm_spec_vers_cmp':TRUE},
{'reference':'kernel-tools-devel-4.14.262-135.489.amzn1', 'cpu':'x86_64', 'release':'ALA', 'rpm_spec_vers_cmp':TRUE},
{'reference':'perf-4.14.262-135.489.amzn1', 'cpu':'i686', 'release':'ALA', 'rpm_spec_vers_cmp':TRUE},
{'reference':'perf-4.14.262-135.489.amzn1', 'cpu':'x86_64', 'release':'ALA', 'rpm_spec_vers_cmp':TRUE},
{'reference':'perf-debuginfo-4.14.262-135.489.amzn1', 'cpu':'i686', 'release':'ALA', 'rpm_spec_vers_cmp':TRUE},
{'reference':'perf-debuginfo-4.14.262-135.489.amzn1', 'cpu':'x86_64', 'release':'ALA', '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_WARNING,
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, "kernel / kernel-debuginfo / kernel-debuginfo-common-x86_64 / etc");
}
Vendor | Product | Version | CPE |
---|---|---|---|
amazon | linux | kernel | p-cpe:/a:amazon:linux:kernel |
amazon | linux | kernel-debuginfo | p-cpe:/a:amazon:linux:kernel-debuginfo |
amazon | linux | kernel-debuginfo-common-i686 | p-cpe:/a:amazon:linux:kernel-debuginfo-common-i686 |
amazon | linux | kernel-debuginfo-common-x86_64 | p-cpe:/a:amazon:linux:kernel-debuginfo-common-x86_64 |
amazon | linux | kernel-devel | p-cpe:/a:amazon:linux:kernel-devel |
amazon | linux | kernel-headers | p-cpe:/a:amazon:linux:kernel-headers |
amazon | linux | kernel-tools | p-cpe:/a:amazon:linux:kernel-tools |
amazon | linux | kernel-tools-debuginfo | p-cpe:/a:amazon:linux:kernel-tools-debuginfo |
amazon | linux | kernel-tools-devel | p-cpe:/a:amazon:linux:kernel-tools-devel |
amazon | linux | perf | p-cpe:/a:amazon:linux:perf |
cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2021-20322
cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2021-28711
cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2021-28712
cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2021-28713
cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2021-28714
cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2021-28715
cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2021-3772
cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2021-4002
cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2021-4155
cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2022-0492
alas.aws.amazon.com/ALAS-2022-1563.html
alas.aws.amazon.com/cve/html/CVE-2021-20322.html
alas.aws.amazon.com/cve/html/CVE-2021-28711.html
alas.aws.amazon.com/cve/html/CVE-2021-28712.html
alas.aws.amazon.com/cve/html/CVE-2021-28713.html
alas.aws.amazon.com/cve/html/CVE-2021-28714.html
alas.aws.amazon.com/cve/html/CVE-2021-28715.html
alas.aws.amazon.com/cve/html/CVE-2021-3772.html
alas.aws.amazon.com/cve/html/CVE-2021-4002.html
alas.aws.amazon.com/cve/html/CVE-2021-4155.html
alas.aws.amazon.com/cve/html/CVE-2022-0492.html