CVSS3
Attack Vector
LOCAL
Attack Complexity
LOW
Privileges Required
NONE
User Interaction
REQUIRED
Scope
CHANGED
Confidentiality Impact
HIGH
Integrity Impact
HIGH
Availability Impact
HIGH
CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:C/C:H/I:H/A:H
AI Score
Confidence
High
EPSS
Percentile
10.3%
The remote Ubuntu 14.04 LTS / 16.04 LTS / 18.04 LTS / 20.04 LTS / 22.04 LTS / 23.10 / 24.04 LTS. host has a package installed that is affected by a vulnerability as referenced in the USN-6756-1 advisory.
It was discovered that less mishandled newline characters in file names. If a user or automated system were tricked into opening specially crafted files, an attacker could possibly use this issue to execute arbitrary commands on the host.
Tenable has extracted the preceding description block directly from the Ubuntu security advisory.
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 80900
##
# (C) Tenable, Inc.
#
# The descriptive text and package checks in this plugin were
# extracted from Ubuntu Security Notice USN-6756-1. The text
# itself is copyright (C) Canonical, Inc. See
# <https://ubuntu.com/security/notices>. Ubuntu(R) is a registered
# trademark of Canonical, Inc.
##
include('compat.inc');
if (description)
{
script_id(194474);
script_version("1.3");
script_set_attribute(attribute:"plugin_modification_date", value:"2024/08/27");
script_cve_id("CVE-2024-32487");
script_xref(name:"USN", value:"6756-1");
script_name(english:"Ubuntu 14.04 LTS / 16.04 LTS / 18.04 LTS / 20.04 LTS / 22.04 LTS / 23.10 / 24.04 LTS. : less vulnerability (USN-6756-1)");
script_set_attribute(attribute:"synopsis", value:
"The remote Ubuntu host is missing a security update.");
script_set_attribute(attribute:"description", value:
"The remote Ubuntu 14.04 LTS / 16.04 LTS / 18.04 LTS / 20.04 LTS / 22.04 LTS / 23.10 / 24.04 LTS. host has a package
installed that is affected by a vulnerability as referenced in the USN-6756-1 advisory.
It was discovered that less mishandled newline characters in file names. If a user or automated system
were tricked into opening specially crafted files, an attacker could possibly use this issue to execute
arbitrary commands on the host.
Tenable has extracted the preceding description block directly from the Ubuntu security advisory.
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://ubuntu.com/security/notices/USN-6756-1");
script_set_attribute(attribute:"solution", value:
"Update the affected less package.");
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:N/UI:R/S:C/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-2024-32487");
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:"2024/04/13");
script_set_attribute(attribute:"patch_publication_date", value:"2024/04/29");
script_set_attribute(attribute:"plugin_publication_date", value:"2024/04/29");
script_set_attribute(attribute:"plugin_type", value:"local");
script_set_attribute(attribute:"cpe", value:"cpe:/o:canonical:ubuntu_linux:14.04:-:lts");
script_set_attribute(attribute:"cpe", value:"cpe:/o:canonical:ubuntu_linux:16.04:-:lts");
script_set_attribute(attribute:"cpe", value:"cpe:/o:canonical:ubuntu_linux:18.04:-:lts");
script_set_attribute(attribute:"cpe", value:"cpe:/o:canonical:ubuntu_linux:20.04:-:lts");
script_set_attribute(attribute:"cpe", value:"cpe:/o:canonical:ubuntu_linux:22.04:-:lts");
script_set_attribute(attribute:"cpe", value:"cpe:/o:canonical:ubuntu_linux:23.10");
script_set_attribute(attribute:"cpe", value:"cpe:/o:canonical:ubuntu_linux:24.04:-:lts.");
script_set_attribute(attribute:"cpe", value:"p-cpe:/a:canonical:ubuntu_linux:less");
script_set_attribute(attribute:"generated_plugin", value:"current");
script_end_attributes();
script_category(ACT_GATHER_INFO);
script_family(english:"Ubuntu Local Security Checks");
script_copyright(english:"Ubuntu Security Notice (C) 2024 Canonical, Inc. / NASL script (C) 2024 and is owned by Tenable, Inc. or an Affiliate thereof.");
script_dependencies("ssh_get_info.nasl", "ubuntu_pro_sub_detect.nasl");
script_require_keys("Host/cpu", "Host/Ubuntu", "Host/Ubuntu/release", "Host/Debian/dpkg-l");
exit(0);
}
include('debian_package.inc');
if ( ! get_kb_item('Host/local_checks_enabled') ) audit(AUDIT_LOCAL_CHECKS_NOT_ENABLED);
var os_release = get_kb_item('Host/Ubuntu/release');
if ( isnull(os_release) ) audit(AUDIT_OS_NOT, 'Ubuntu');
os_release = chomp(os_release);
if (! ('14.04' >< os_release || '16.04' >< os_release || '18.04' >< os_release || '20.04' >< os_release || '22.04' >< os_release || '23.10' >< os_release || '24.04' >< os_release)) audit(AUDIT_OS_NOT, 'Ubuntu 14.04 / 16.04 / 18.04 / 20.04 / 22.04 / 23.10 / 24.04', 'Ubuntu ' + os_release);
if ( ! get_kb_item('Host/Debian/dpkg-l') ) 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) audit(AUDIT_LOCAL_CHECKS_NOT_IMPLEMENTED, 'Ubuntu', cpu);
var ubuntu_pro_detected = get_kb_item('Host/Ubuntu/Pro/Services/esm-apps');
ubuntu_pro_detected = !empty_or_null(ubuntu_pro_detected);
var pro_caveat_needed = FALSE;
var pkgs = [
{'osver': '14.04', 'pkgname': 'less', 'pkgver': '458-2ubuntu0.1~esm1', 'ubuntu_pro': TRUE},
{'osver': '16.04', 'pkgname': 'less', 'pkgver': '481-2.1ubuntu0.2+esm2', 'ubuntu_pro': TRUE},
{'osver': '18.04', 'pkgname': 'less', 'pkgver': '487-0.1ubuntu0.1~esm2', 'ubuntu_pro': TRUE},
{'osver': '20.04', 'pkgname': 'less', 'pkgver': '551-1ubuntu0.3', 'ubuntu_pro': FALSE},
{'osver': '22.04', 'pkgname': 'less', 'pkgver': '590-1ubuntu0.22.04.3', 'ubuntu_pro': FALSE},
{'osver': '23.10', 'pkgname': 'less', 'pkgver': '590-2ubuntu0.23.10.2', 'ubuntu_pro': FALSE},
{'osver': '24.04', 'pkgname': 'less', 'pkgver': '590-2ubuntu2.1', 'ubuntu_pro': FALSE}
];
var flag = 0;
foreach var package_array ( pkgs ) {
var osver = NULL;
var pkgname = NULL;
var pkgver = NULL;
if (!empty_or_null(package_array['osver'])) osver = package_array['osver'];
if (!empty_or_null(package_array['pkgname'])) pkgname = package_array['pkgname'];
if (!empty_or_null(package_array['pkgver'])) pkgver = package_array['pkgver'];
var pro_required = NULL;
if (!empty_or_null(package_array['ubuntu_pro'])) pro_required = package_array['ubuntu_pro'];
if (osver && pkgname && pkgver) {
if (ubuntu_check(osver:osver, pkgname:pkgname, pkgver:pkgver)) {
flag++;
if (!ubuntu_pro_detected && !pro_caveat_needed) pro_caveat_needed = pro_required;
}
}
}
if (flag)
{
var extra = '';
if (pro_caveat_needed) {
extra += 'NOTE: This vulnerability check contains fixes that apply to packages only \n';
extra += 'available in Ubuntu ESM repositories. Access to these package security updates \n';
extra += 'require an Ubuntu Pro subscription.\n\n';
}
extra += ubuntu_report_get();
security_report_v4(
port : 0,
severity : SECURITY_HOLE,
extra : extra
);
exit(0);
}
else
{
var tested = ubuntu_pkg_tests_get();
if (tested) audit(AUDIT_PACKAGE_NOT_AFFECTED, tested);
else audit(AUDIT_PACKAGE_NOT_INSTALLED, 'less');
}
CVSS3
Attack Vector
LOCAL
Attack Complexity
LOW
Privileges Required
NONE
User Interaction
REQUIRED
Scope
CHANGED
Confidentiality Impact
HIGH
Integrity Impact
HIGH
Availability Impact
HIGH
CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:C/C:H/I:H/A:H
AI Score
Confidence
High
EPSS
Percentile
10.3%