10 High
CVSS2
Attack Vector
NETWORK
Attack Complexity
LOW
Authentication
NONE
Confidentiality Impact
COMPLETE
Integrity Impact
COMPLETE
Availability Impact
COMPLETE
AV:N/AC:L/Au:N/C:C/I:C/A:C
9.8 High
CVSS3
Attack Vector
NETWORK
Attack Complexity
LOW
Privileges Required
NONE
User Interaction
NONE
Scope
UNCHANGED
Confidentiality Impact
HIGH
Integrity Impact
HIGH
Availability Impact
HIGH
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
0.006 Low
EPSS
Percentile
77.9%
The remote Fedora 33 host has a package installed that is affected by multiple vulnerabilities as referenced in the FEDORA-2021-3342569a0f advisory.
A vulnerability was discovered in the PyYAML library in versions before 5.3.1, where it is susceptible to arbitrary code execution when it processes untrusted YAML files through the full_load method or with the FullLoader loader. Applications that use the library to process untrusted input may be vulnerable to this flaw. An attacker could use this flaw to execute arbitrary code on the system by abusing the python/object/new constructor. (CVE-2020-1747)
A vulnerability was discovered in the PyYAML library in versions before 5.4, where it is susceptible to arbitrary code execution when it processes untrusted YAML files through the full_load method or with the FullLoader loader. Applications that use the library to process untrusted input may be vulnerable to this flaw. This flaw allows an attacker to execute arbitrary code on the system by abusing the python/object/new constructor. This flaw is due to an incomplete fix for CVE-2020-1747. (CVE-2020-14343)
Note that Nessus has not tested for this issue but has instead relied only on the application’s self-reported version number.
##
# (C) Tenable Network Security, Inc.
##
# The descriptive text and package checks in this plugin were
# extracted from Fedora Security Advisory FEDORA-2021-3342569a0f
#
include('compat.inc');
if (description)
{
script_id(145367);
script_version("1.4");
script_set_attribute(attribute:"plugin_modification_date", value:"2021/10/15");
script_cve_id("CVE-2020-14343", "CVE-2020-1747");
script_xref(name:"FEDORA", value:"2021-3342569a0f");
script_xref(name:"IAVA", value:"2021-A-0463");
script_name(english:"Fedora 33 : PyYAML (2021-3342569a0f)");
script_set_attribute(attribute:"synopsis", value:
"The remote Fedora host is missing one or more security updates.");
script_set_attribute(attribute:"description", value:
"The remote Fedora 33 host has a package installed that is affected by multiple vulnerabilities as referenced in the
FEDORA-2021-3342569a0f advisory.
- A vulnerability was discovered in the PyYAML library in versions before 5.3.1, where it is susceptible to
arbitrary code execution when it processes untrusted YAML files through the full_load method or with the
FullLoader loader. Applications that use the library to process untrusted input may be vulnerable to this
flaw. An attacker could use this flaw to execute arbitrary code on the system by abusing the
python/object/new constructor. (CVE-2020-1747)
- A vulnerability was discovered in the PyYAML library in versions before 5.4, where it is susceptible to
arbitrary code execution when it processes untrusted YAML files through the full_load method or with the
FullLoader loader. Applications that use the library to process untrusted input may be vulnerable to this
flaw. This flaw allows an attacker to execute arbitrary code on the system by abusing the
python/object/new constructor. This flaw is due to an incomplete fix for CVE-2020-1747. (CVE-2020-14343)
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://bodhi.fedoraproject.org/updates/FEDORA-2021-3342569a0f");
script_set_attribute(attribute:"solution", value:
"Update the affected PyYAML package.");
script_set_cvss_base_vector("CVSS2#AV:N/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:N/AC:L/PR:N/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-2020-1747");
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:"2020/03/19");
script_set_attribute(attribute:"patch_publication_date", value:"2021/01/21");
script_set_attribute(attribute:"plugin_publication_date", value:"2021/01/25");
script_set_attribute(attribute:"plugin_type", value:"local");
script_set_attribute(attribute:"cpe", value:"cpe:/o:fedoraproject:fedora:33");
script_set_attribute(attribute:"cpe", value:"p-cpe:/a:fedoraproject:fedora:PyYAML");
script_set_attribute(attribute:"stig_severity", value:"I");
script_end_attributes();
script_category(ACT_GATHER_INFO);
script_family(english:"Fedora Local Security Checks");
script_copyright(english:"This script is Copyright (C) 2021 and is owned by Tenable, Inc. or an Affiliate thereof.");
script_dependencies("ssh_get_info.nasl");
script_require_keys("Host/local_checks_enabled", "Host/RedHat/release", "Host/RedHat/rpm-list");
exit(0);
}
include('audit.inc');
include('global_settings.inc');
include('rpm.inc');
if (!get_kb_item('Host/local_checks_enabled')) audit(AUDIT_LOCAL_CHECKS_NOT_ENABLED);
release = get_kb_item('Host/RedHat/release');
if (isnull(release) || 'Fedora' >!< release) audit(AUDIT_OS_NOT, 'Fedora');
os_ver = pregmatch(pattern: "Fedora.*release ([0-9]+)", string:release);
if (isnull(os_ver)) audit(AUDIT_UNKNOWN_APP_VER, 'Fedora');
os_ver = os_ver[1];
if (! preg(pattern:"^33([^0-9]|$)", string:os_ver)) audit(AUDIT_OS_NOT, 'Fedora 33', 'Fedora ' + os_ver);
if (!get_kb_item('Host/RedHat/rpm-list')) audit(AUDIT_PACKAGE_LIST_MISSING);
cpu = get_kb_item('Host/cpu');
if (isnull(cpu)) audit(AUDIT_UNKNOWN_ARCH);
if ('x86_64' >!< cpu && cpu !~ "^i[3-6]86$" && 's390' >!< cpu && 'aarch64' >!< cpu) audit(AUDIT_LOCAL_CHECKS_NOT_IMPLEMENTED, 'Fedora', cpu);
pkgs = [
{'reference':'PyYAML-5.4.1-1.fc33', 'release':'FC33', 'rpm_spec_vers_cmp':TRUE}
];
flag = 0;
foreach package_array ( pkgs ) {
reference = NULL;
release = NULL;
sp = NULL;
cpu = NULL;
el_string = NULL;
rpm_spec_vers_cmp = NULL;
epoch = NULL;
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['sp'])) sp = package_array['sp'];
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['epoch'])) epoch = package_array['epoch'];
if (!empty_or_null(package_array['allowmaj'])) allowmaj = package_array['allowmaj'];
if (reference && release) {
if (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)) flag++;
}
}
if (flag)
{
security_report_v4(
port : 0,
severity : SECURITY_HOLE,
extra : rpm_report_get()
);
exit(0);
}
else
{
tested = pkg_tests_get();
if (tested) audit(AUDIT_PACKAGE_NOT_AFFECTED, tested);
else audit(AUDIT_PACKAGE_NOT_INSTALLED, 'PyYAML');
}
Vendor | Product | Version | CPE |
---|---|---|---|
fedoraproject | fedora | 33 | cpe:/o:fedoraproject:fedora:33 |
fedoraproject | fedora | pyyaml | p-cpe:/a:fedoraproject:fedora:pyyaml |
10 High
CVSS2
Attack Vector
NETWORK
Attack Complexity
LOW
Authentication
NONE
Confidentiality Impact
COMPLETE
Integrity Impact
COMPLETE
Availability Impact
COMPLETE
AV:N/AC:L/Au:N/C:C/I:C/A:C
9.8 High
CVSS3
Attack Vector
NETWORK
Attack Complexity
LOW
Privileges Required
NONE
User Interaction
NONE
Scope
UNCHANGED
Confidentiality Impact
HIGH
Integrity Impact
HIGH
Availability Impact
HIGH
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
0.006 Low
EPSS
Percentile
77.9%