CVSS2
Attack Vector
LOCAL
Attack Complexity
MEDIUM
Authentication
NONE
Confidentiality Impact
PARTIAL
Integrity Impact
PARTIAL
Availability Impact
PARTIAL
AV:L/AC:M/Au:N/C:P/I:P/A:P
CVSS3
Attack Vector
LOCAL
Attack Complexity
LOW
Privileges Required
LOW
User Interaction
NONE
Scope
UNCHANGED
Confidentiality Impact
HIGH
Integrity Impact
HIGH
Availability Impact
HIGH
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
AI Score
Confidence
Low
EPSS
Percentile
40.7%
The remote Redhat Enterprise Linux 8 host has a package installed that is affected by multiple vulnerabilities as referenced in the RHSA-2021:1723 advisory.
The sudo packages contain the sudo utility which allows system administrators to provide certain users with the permission to execute privileged commands, which are used for system management purposes, without having to log in as root.
Security Fix(es):
* sudo: symbolic link attack in SELinux-enabled sudoedit (CVE-2021-23240)
* sudo: possible directory existence test due to race condition in sudoedit (CVE-2021-23239)
For more details about the security issue(s), including the impact, a CVSS score, acknowledgments, and other related information, refer to the CVE page(s) listed in the References section.
Additional Changes:
For detailed information on changes in this release, see the Red Hat Enterprise Linux 8.4 Release Notes linked from the References section.
Tenable has extracted the preceding description block directly from the Red Hat Enterprise Linux security advisory.
Note that Nessus has not tested for these issues but has instead relied only on the application’s self-reported version number.
#%NASL_MIN_LEVEL 70300
##
# (C) Tenable, Inc.
#
# The descriptive text and package checks in this plugin were
# extracted from Red Hat Security Advisory RHSA-2021:1723. The text
# itself is copyright (C) Red Hat, Inc.
##
include('deprecated_nasl_level.inc');
include('compat.inc');
if (description)
{
script_id(149683);
script_version("1.10");
script_set_attribute(attribute:"plugin_modification_date", value:"2024/06/03");
script_cve_id("CVE-2021-23239", "CVE-2021-23240");
script_xref(name:"IAVA", value:"2021-A-0053");
script_xref(name:"RHSA", value:"2021:1723");
script_name(english:"RHEL 8 : sudo (RHSA-2021:1723)");
script_set_attribute(attribute:"synopsis", value:
"The remote Red Hat host is missing one or more security updates for sudo.");
script_set_attribute(attribute:"description", value:
"The remote Redhat Enterprise Linux 8 host has a package installed that is affected by multiple vulnerabilities as
referenced in the RHSA-2021:1723 advisory.
The sudo packages contain the sudo utility which allows system administrators to provide certain users
with the permission to execute privileged commands, which are used for system management purposes, without
having to log in as root.
Security Fix(es):
* sudo: symbolic link attack in SELinux-enabled sudoedit (CVE-2021-23240)
* sudo: possible directory existence test due to race condition in sudoedit (CVE-2021-23239)
For more details about the security issue(s), including the impact, a CVSS score, acknowledgments, and
other related information, refer to the CVE page(s) listed in the References section.
Additional Changes:
For detailed information on changes in this release, see the Red Hat Enterprise Linux 8.4 Release Notes
linked from the References section.
Tenable has extracted the preceding description block directly from the Red Hat Enterprise Linux security advisory.
Note that Nessus has not tested for these issues but has instead relied only on the application's self-reported version
number.");
# https://access.redhat.com/documentation/en-us/red_hat_enterprise_linux/8/html/8.4_release_notes/
script_set_attribute(attribute:"see_also", value:"http://www.nessus.org/u?862005a9");
# https://access.redhat.com/security/data/csaf/v2/advisories/2021/rhsa-2021_1723.json
script_set_attribute(attribute:"see_also", value:"http://www.nessus.org/u?a56256f1");
script_set_attribute(attribute:"see_also", value:"https://access.redhat.com/security/updates/classification/#low");
script_set_attribute(attribute:"see_also", value:"https://access.redhat.com/errata/RHSA-2021:1723");
script_set_attribute(attribute:"see_also", value:"https://bugzilla.redhat.com/show_bug.cgi?id=1915052");
script_set_attribute(attribute:"see_also", value:"https://bugzilla.redhat.com/show_bug.cgi?id=1915053");
script_set_attribute(attribute:"see_also", value:"https://bugzilla.redhat.com/show_bug.cgi?id=1923825");
script_set_attribute(attribute:"solution", value:
"Update the RHEL sudo package based on the guidance in RHSA-2021:1723.");
script_set_cvss_base_vector("CVSS2#AV:L/AC:M/Au:N/C:P/I:P/A:P");
script_set_cvss_temporal_vector("CVSS2#E:POC/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:P/RL:O/RC:C");
script_set_attribute(attribute:"cvss_score_source", value:"CVE-2021-23240");
script_set_attribute(attribute:"exploitability_ease", value:"Exploits are available");
script_set_attribute(attribute:"exploit_available", value:"true");
script_cwe_id(59, 203);
script_set_attribute(attribute:"vendor_severity", value:"Low");
script_set_attribute(attribute:"vuln_publication_date", value:"2021/01/12");
script_set_attribute(attribute:"patch_publication_date", value:"2021/05/18");
script_set_attribute(attribute:"plugin_publication_date", value:"2021/05/19");
script_set_attribute(attribute:"plugin_type", value:"local");
script_set_attribute(attribute:"cpe", value:"cpe:/o:redhat:enterprise_linux:8");
script_set_attribute(attribute:"cpe", value:"p-cpe:/a:redhat:enterprise_linux:sudo");
script_set_attribute(attribute:"generated_plugin", value:"current");
script_set_attribute(attribute:"stig_severity", value:"I");
script_end_attributes();
script_category(ACT_GATHER_INFO);
script_family(english:"Red Hat Local Security Checks");
script_copyright(english:"This script is Copyright (C) 2021-2024 and is owned by Tenable, Inc. or an Affiliate thereof.");
script_dependencies("ssh_get_info.nasl", "redhat_repos.nasl");
script_require_keys("Host/local_checks_enabled", "Host/RedHat/release", "Host/RedHat/rpm-list", "Host/cpu");
exit(0);
}
include('rpm.inc');
include('rhel.inc');
if (!get_kb_item('Host/local_checks_enabled')) audit(AUDIT_LOCAL_CHECKS_NOT_ENABLED);
var os_release = get_kb_item('Host/RedHat/release');
if (isnull(os_release) || 'Red Hat' >!< os_release) audit(AUDIT_OS_NOT, 'Red Hat');
var os_ver = pregmatch(pattern: "Red Hat Enterprise Linux.*release ([0-9]+(\.[0-9]+)?)", string:os_release);
if (isnull(os_ver)) audit(AUDIT_UNKNOWN_APP_VER, 'Red Hat');
os_ver = os_ver[1];
if (!rhel_check_release(operator: 'ge', os_version: os_ver, rhel_version: '8')) audit(AUDIT_OS_NOT, 'Red Hat 8.x', 'Red Hat ' + os_ver);
if (!get_kb_item('Host/RedHat/rpm-list')) audit(AUDIT_PACKAGE_LIST_MISSING);
var cpu = get_kb_item('Host/cpu');
if (isnull(cpu)) audit(AUDIT_UNKNOWN_ARCH);
if ('x86_64' >!< cpu && cpu !~ "^i[3-6]86$" && 's390' >!< cpu && 'aarch64' >!< cpu && 'ppc' >!< cpu) audit(AUDIT_LOCAL_CHECKS_NOT_IMPLEMENTED, 'Red Hat', cpu);
var constraints = [
{
'repo_relative_urls': [
'content/dist/rhel8/8.10/aarch64/baseos/debug',
'content/dist/rhel8/8.10/aarch64/baseos/os',
'content/dist/rhel8/8.10/aarch64/baseos/source/SRPMS',
'content/dist/rhel8/8.10/ppc64le/baseos/debug',
'content/dist/rhel8/8.10/ppc64le/baseos/os',
'content/dist/rhel8/8.10/ppc64le/baseos/source/SRPMS',
'content/dist/rhel8/8.10/s390x/baseos/debug',
'content/dist/rhel8/8.10/s390x/baseos/os',
'content/dist/rhel8/8.10/s390x/baseos/source/SRPMS',
'content/dist/rhel8/8.10/x86_64/baseos/debug',
'content/dist/rhel8/8.10/x86_64/baseos/os',
'content/dist/rhel8/8.10/x86_64/baseos/source/SRPMS',
'content/dist/rhel8/8.6/aarch64/baseos/debug',
'content/dist/rhel8/8.6/aarch64/baseos/os',
'content/dist/rhel8/8.6/aarch64/baseos/source/SRPMS',
'content/dist/rhel8/8.6/ppc64le/baseos/debug',
'content/dist/rhel8/8.6/ppc64le/baseos/os',
'content/dist/rhel8/8.6/ppc64le/baseos/source/SRPMS',
'content/dist/rhel8/8.6/s390x/baseos/debug',
'content/dist/rhel8/8.6/s390x/baseos/os',
'content/dist/rhel8/8.6/s390x/baseos/source/SRPMS',
'content/dist/rhel8/8.6/x86_64/baseos/debug',
'content/dist/rhel8/8.6/x86_64/baseos/os',
'content/dist/rhel8/8.6/x86_64/baseos/source/SRPMS',
'content/dist/rhel8/8.8/aarch64/baseos/debug',
'content/dist/rhel8/8.8/aarch64/baseos/os',
'content/dist/rhel8/8.8/aarch64/baseos/source/SRPMS',
'content/dist/rhel8/8.8/ppc64le/baseos/debug',
'content/dist/rhel8/8.8/ppc64le/baseos/os',
'content/dist/rhel8/8.8/ppc64le/baseos/source/SRPMS',
'content/dist/rhel8/8.8/s390x/baseos/debug',
'content/dist/rhel8/8.8/s390x/baseos/os',
'content/dist/rhel8/8.8/s390x/baseos/source/SRPMS',
'content/dist/rhel8/8.8/x86_64/baseos/debug',
'content/dist/rhel8/8.8/x86_64/baseos/os',
'content/dist/rhel8/8.8/x86_64/baseos/source/SRPMS',
'content/dist/rhel8/8.9/aarch64/baseos/debug',
'content/dist/rhel8/8.9/aarch64/baseos/os',
'content/dist/rhel8/8.9/aarch64/baseos/source/SRPMS',
'content/dist/rhel8/8.9/ppc64le/baseos/debug',
'content/dist/rhel8/8.9/ppc64le/baseos/os',
'content/dist/rhel8/8.9/ppc64le/baseos/source/SRPMS',
'content/dist/rhel8/8.9/s390x/baseos/debug',
'content/dist/rhel8/8.9/s390x/baseos/os',
'content/dist/rhel8/8.9/s390x/baseos/source/SRPMS',
'content/dist/rhel8/8.9/x86_64/baseos/debug',
'content/dist/rhel8/8.9/x86_64/baseos/os',
'content/dist/rhel8/8.9/x86_64/baseos/source/SRPMS',
'content/dist/rhel8/8/aarch64/baseos/debug',
'content/dist/rhel8/8/aarch64/baseos/os',
'content/dist/rhel8/8/aarch64/baseos/source/SRPMS',
'content/dist/rhel8/8/ppc64le/baseos/debug',
'content/dist/rhel8/8/ppc64le/baseos/os',
'content/dist/rhel8/8/ppc64le/baseos/source/SRPMS',
'content/dist/rhel8/8/s390x/baseos/debug',
'content/dist/rhel8/8/s390x/baseos/os',
'content/dist/rhel8/8/s390x/baseos/source/SRPMS',
'content/dist/rhel8/8/x86_64/baseos/debug',
'content/dist/rhel8/8/x86_64/baseos/os',
'content/dist/rhel8/8/x86_64/baseos/source/SRPMS'
],
'pkgs': [
{'reference':'sudo-1.8.29-7.el8', 'release':'8', 'rpm_spec_vers_cmp':TRUE}
]
}
];
var applicable_repo_urls = rhel_determine_applicable_repository_urls(constraints:constraints);
if(applicable_repo_urls == RHEL_REPOS_NO_OVERLAP_MESSAGE) exit(0, RHEL_REPO_NOT_ENABLED);
var flag = 0;
foreach var constraint_array ( constraints ) {
var repo_relative_urls = NULL;
if (!empty_or_null(constraint_array['repo_relative_urls'])) repo_relative_urls = constraint_array['repo_relative_urls'];
foreach var pkg ( constraint_array['pkgs'] ) {
var reference = NULL;
var _release = NULL;
var sp = NULL;
var _cpu = NULL;
var el_string = NULL;
var rpm_spec_vers_cmp = NULL;
var epoch = NULL;
var allowmaj = NULL;
var exists_check = NULL;
var cves = NULL;
if (!empty_or_null(pkg['reference'])) reference = pkg['reference'];
if (!empty_or_null(pkg['release'])) _release = 'RHEL' + pkg['release'];
if (!empty_or_null(pkg['sp'])) sp = pkg['sp'];
if (!empty_or_null(pkg['cpu'])) _cpu = pkg['cpu'];
if (!empty_or_null(pkg['el_string'])) el_string = pkg['el_string'];
if (!empty_or_null(pkg['rpm_spec_vers_cmp'])) rpm_spec_vers_cmp = pkg['rpm_spec_vers_cmp'];
if (!empty_or_null(pkg['epoch'])) epoch = pkg['epoch'];
if (!empty_or_null(pkg['allowmaj'])) allowmaj = pkg['allowmaj'];
if (!empty_or_null(pkg['exists_check'])) exists_check = pkg['exists_check'];
if (!empty_or_null(pkg['cves'])) cves = pkg['cves'];
if (reference &&
_release &&
rhel_decide_repo_relative_url_check(required_repo_url_list:repo_relative_urls) &&
(applicable_repo_urls || (!exists_check || rpm_exists(release:_release, rpm:exists_check))) &&
rpm_check(release:_release, sp:sp, cpu:_cpu, reference:reference, epoch:epoch, el_string:el_string, rpm_spec_vers_cmp:rpm_spec_vers_cmp, allowmaj:allowmaj, cves:cves)) flag++;
}
}
if (flag)
{
var extra = NULL;
if (isnull(applicable_repo_urls) || !applicable_repo_urls) extra = rpm_report_get() + redhat_report_repo_caveat();
else extra = rpm_report_get();
security_report_v4(
port : 0,
severity : SECURITY_WARNING,
extra : extra
);
exit(0);
}
else
{
var tested = pkg_tests_get();
if (tested) audit(AUDIT_PACKAGE_NOT_AFFECTED, tested);
else audit(AUDIT_PACKAGE_NOT_INSTALLED, 'sudo');
}
Vendor | Product | Version | CPE |
---|---|---|---|
redhat | enterprise_linux | 8 | cpe:/o:redhat:enterprise_linux:8 |
redhat | enterprise_linux | sudo | p-cpe:/a:redhat:enterprise_linux:sudo |
cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2021-23239
cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2021-23240
www.nessus.org/u?862005a9
www.nessus.org/u?a56256f1
access.redhat.com/errata/RHSA-2021:1723
access.redhat.com/security/updates/classification/#low
bugzilla.redhat.com/show_bug.cgi?id=1915052
bugzilla.redhat.com/show_bug.cgi?id=1915053
bugzilla.redhat.com/show_bug.cgi?id=1923825
CVSS2
Attack Vector
LOCAL
Attack Complexity
MEDIUM
Authentication
NONE
Confidentiality Impact
PARTIAL
Integrity Impact
PARTIAL
Availability Impact
PARTIAL
AV:L/AC:M/Au:N/C:P/I:P/A:P
CVSS3
Attack Vector
LOCAL
Attack Complexity
LOW
Privileges Required
LOW
User Interaction
NONE
Scope
UNCHANGED
Confidentiality Impact
HIGH
Integrity Impact
HIGH
Availability Impact
HIGH
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
AI Score
Confidence
Low
EPSS
Percentile
40.7%