CVSS2
Attack Vector
NETWORK
Attack Complexity
LOW
Authentication
NONE
Confidentiality Impact
NONE
Integrity Impact
PARTIAL
Availability Impact
NONE
AV:N/AC:L/Au:N/C:N/I:P/A:N
CVSS3
Attack Vector
NETWORK
Attack Complexity
LOW
Privileges Required
NONE
User Interaction
NONE
Scope
CHANGED
Confidentiality Impact
HIGH
Integrity Impact
HIGH
Availability Impact
NONE
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:N
EPSS
Percentile
77.9%
The remote Ubuntu 16.04 ESM / 18.04 ESM / 20.04 LTS / 22.04 LTS host has a package installed that is affected by a vulnerability as referenced in the USN-6239-1 advisory.
ecdsa_verify_[prepare_]legacy()
does not check whether the signature values r
and s
are non-zero. A signature consisting only of zeroes is always considered valid, making it trivial to forge signatures.ecdsa_verify_list_legacy()
will accept an arbitrary number of such forged signatures. Both the ecdsautil verify
CLI command and the libecdsautil library are affected. The issue has been fixed in ecdsautils 0.4.1. All older versions of ecdsautils (including versions before the split into a library and a CLI utility) are vulnerable. (CVE-2022-24884)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-6239-1. 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(178636);
script_version("1.0");
script_set_attribute(attribute:"plugin_modification_date", value:"2023/07/20");
script_cve_id("CVE-2022-24884");
script_xref(name:"USN", value:"6239-1");
script_name(english:"Ubuntu 16.04 ESM / 18.04 ESM / 20.04 LTS / 22.04 LTS : ECDSA Util vulnerability (USN-6239-1)");
script_set_attribute(attribute:"synopsis", value:
"The remote Ubuntu host is missing a security update.");
script_set_attribute(attribute:"description", value:
"The remote Ubuntu 16.04 ESM / 18.04 ESM / 20.04 LTS / 22.04 LTS host has a package installed that is affected by a
vulnerability as referenced in the USN-6239-1 advisory.
- ecdsautils is a tiny collection of programs used for ECDSA (keygen, sign, verify).
`ecdsa_verify_[prepare_]legacy()` does not check whether the signature values `r` and `s` are non-zero. A
signature consisting only of zeroes is always considered valid, making it trivial to forge signatures.
Requiring multiple signatures from different public keys does not mitigate the issue:
`ecdsa_verify_list_legacy()` will accept an arbitrary number of such forged signatures. Both the
`ecdsautil verify` CLI command and the libecdsautil library are affected. The issue has been fixed in
ecdsautils 0.4.1. All older versions of ecdsautils (including versions before the split into a library and
a CLI utility) are vulnerable. (CVE-2022-24884)
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-6239-1");
script_set_attribute(attribute:"solution", value:
"Update the affected ecdsautils package.");
script_set_cvss_base_vector("CVSS2#AV:N/AC:L/Au:N/C:N/I:P/A:N");
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:N/I:H/A:N");
script_set_cvss3_temporal_vector("CVSS:3.0/E:U/RL:O/RC:C");
script_set_attribute(attribute:"cvss_score_source", value:"CVE-2022-24884");
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:"2022/05/06");
script_set_attribute(attribute:"patch_publication_date", value:"2023/07/20");
script_set_attribute(attribute:"plugin_publication_date", value:"2023/07/20");
script_set_attribute(attribute:"plugin_type", value:"local");
script_set_attribute(attribute:"cpe", value:"cpe:/o:canonical:ubuntu_linux:16.04:-:esm");
script_set_attribute(attribute:"cpe", value:"cpe:/o:canonical:ubuntu_linux:18.04:-:esm");
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:"p-cpe:/a:canonical:ubuntu_linux:ecdsautils");
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) 2023 Canonical, Inc. / NASL script (C) 2023 and is owned by Tenable, Inc. or an Affiliate thereof.");
script_dependencies("ssh_get_info.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 (! ('16.04' >< os_release || '18.04' >< os_release || '20.04' >< os_release || '22.04' >< os_release)) audit(AUDIT_OS_NOT, 'Ubuntu 16.04 / 18.04 / 20.04 / 22.04', '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 pkgs = [
{'osver': '16.04', 'pkgname': 'ecdsautils', 'pkgver': '0.3.2+git20151018-2ubuntu0.16.04.1~esm1'},
{'osver': '18.04', 'pkgname': 'ecdsautils', 'pkgver': '0.3.2+git20151018-2ubuntu0.18.04.1~esm1'},
{'osver': '20.04', 'pkgname': 'ecdsautils', 'pkgver': '0.3.2+git20151018-2+deb10u1build0.20.04.1'},
{'osver': '22.04', 'pkgname': 'ecdsautils', 'pkgver': '0.3.2+git20151018-2+deb10u1build0.22.04.1'}
];
var flag = 0;
foreach 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'];
if (osver && pkgname && pkgver) {
if (ubuntu_check(osver:osver, pkgname:pkgname, pkgver:pkgver)) flag++;
}
}
if (flag)
{
security_report_v4(
port : 0,
severity : SECURITY_WARNING,
extra : ubuntu_report_get()
);
exit(0);
}
else
{
var tested = ubuntu_pkg_tests_get();
if (tested) audit(AUDIT_PACKAGE_NOT_AFFECTED, tested);
else audit(AUDIT_PACKAGE_NOT_INSTALLED, 'ecdsautils');
}
CVSS2
Attack Vector
NETWORK
Attack Complexity
LOW
Authentication
NONE
Confidentiality Impact
NONE
Integrity Impact
PARTIAL
Availability Impact
NONE
AV:N/AC:L/Au:N/C:N/I:P/A:N
CVSS3
Attack Vector
NETWORK
Attack Complexity
LOW
Privileges Required
NONE
User Interaction
NONE
Scope
CHANGED
Confidentiality Impact
HIGH
Integrity Impact
HIGH
Availability Impact
NONE
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:N
EPSS
Percentile
77.9%