CVSS2
Attack Vector
NETWORK
Attack Complexity
LOW
Authentication
NONE
Confidentiality Impact
NONE
Integrity Impact
NONE
Availability Impact
PARTIAL
AV:N/AC:L/Au:N/C:N/I:N/A:P
CVSS3
Attack Vector
NETWORK
Attack Complexity
LOW
Privileges Required
NONE
User Interaction
NONE
Scope
UNCHANGED
Confidentiality Impact
NONE
Integrity Impact
NONE
Availability Impact
HIGH
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
AI Score
Confidence
High
EPSS
Percentile
82.1%
The remote Debian 10 host has packages installed that are affected by multiple vulnerabilities as referenced in the dla-3634 advisory.
A flaw was found in the way NSS handled CCS (ChangeCipherSpec) messages in TLS 1.3. This flaw allows a remote attacker to send multiple CCS messages, causing a denial of service for servers compiled with the NSS library. The highest threat from this vulnerability is to system availability. This flaw affects NSS versions before 3.58. (CVE-2020-25648)
new tlsfuzzer code can still detect timing issues in RSA operations (CVE-2023-4421) (CVE-2023-4421)
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 80900
#
# (C) Tenable, Inc.
#
# The descriptive text and package checks in this plugin were
# extracted from Debian Security Advisory dla-3634. The text
# itself is copyright (C) Software in the Public Interest, Inc.
#
include('compat.inc');
if (description)
{
script_id(183996);
script_version("1.1");
script_set_attribute(attribute:"plugin_modification_date", value:"2023/12/22");
script_cve_id("CVE-2020-25648", "CVE-2023-4421");
script_name(english:"Debian DLA-3634-1 : nss - LTS security update");
script_set_attribute(attribute:"synopsis", value:
"The remote Debian host is missing one or more security-related updates.");
script_set_attribute(attribute:"description", value:
"The remote Debian 10 host has packages installed that are affected by multiple vulnerabilities as referenced in the
dla-3634 advisory.
- A flaw was found in the way NSS handled CCS (ChangeCipherSpec) messages in TLS 1.3. This flaw allows a
remote attacker to send multiple CCS messages, causing a denial of service for servers compiled with the
NSS library. The highest threat from this vulnerability is to system availability. This flaw affects NSS
versions before 3.58. (CVE-2020-25648)
- new tlsfuzzer code can still detect timing issues in RSA operations (CVE-2023-4421) (CVE-2023-4421)
Note that Nessus has not tested for these issues but has instead relied only on the application's self-reported version
number.");
script_set_attribute(attribute:"see_also", value:"https://security-tracker.debian.org/tracker/source-package/nss");
script_set_attribute(attribute:"see_also", value:"https://www.debian.org/lts/security/2023/dla-3634");
script_set_attribute(attribute:"see_also", value:"https://security-tracker.debian.org/tracker/CVE-2020-25648");
script_set_attribute(attribute:"see_also", value:"https://security-tracker.debian.org/tracker/CVE-2023-4421");
script_set_attribute(attribute:"see_also", value:"https://packages.debian.org/source/buster/nss");
script_set_attribute(attribute:"solution", value:
"Upgrade the nss packages.
For Debian 10 buster, these problems have been fixed in version 2");
script_set_cvss_base_vector("CVSS2#AV:N/AC:L/Au:N/C:N/I:N/A:P");
script_set_cvss_temporal_vector("CVSS2#E:F/RL:OF/RC:C");
script_set_cvss3_base_vector("CVSS:3.0/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N");
script_set_cvss3_temporal_vector("CVSS:3.0/E:F/RL:O/RC:C");
script_set_attribute(attribute:"cvss_score_source", value:"CVE-2020-25648");
script_set_attribute(attribute:"cvss3_score_source", value:"CVE-2023-4421");
script_set_attribute(attribute:"exploitability_ease", value:"Exploits are available");
script_set_attribute(attribute:"exploit_available", value:"true");
script_set_attribute(attribute:"vuln_publication_date", value:"2020/10/20");
script_set_attribute(attribute:"patch_publication_date", value:"2023/10/28");
script_set_attribute(attribute:"plugin_publication_date", value:"2023/10/28");
script_set_attribute(attribute:"plugin_type", value:"local");
script_set_attribute(attribute:"cpe", value:"p-cpe:/a:debian:debian_linux:libnss3");
script_set_attribute(attribute:"cpe", value:"p-cpe:/a:debian:debian_linux:libnss3-dev");
script_set_attribute(attribute:"cpe", value:"p-cpe:/a:debian:debian_linux:libnss3-tools");
script_set_attribute(attribute:"cpe", value:"cpe:/o:debian:debian_linux:10.0");
script_set_attribute(attribute:"generated_plugin", value:"current");
script_end_attributes();
script_category(ACT_GATHER_INFO);
script_family(english:"Debian Local Security Checks");
script_copyright(english:"This script is Copyright (C) 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/Debian/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);
if (!get_kb_item("Host/Debian/dpkg-l")) audit(AUDIT_PACKAGE_LIST_MISSING);
var debian_release = get_kb_item('Host/Debian/release');
if ( isnull(debian_release) ) audit(AUDIT_OS_NOT, 'Debian');
debian_release = chomp(debian_release);
if (! preg(pattern:"^(10)\.[0-9]+", string:debian_release)) audit(AUDIT_OS_NOT, 'Debian 10.0', 'Debian ' + debian_release);
var cpu = get_kb_item('Host/cpu');
if (isnull(cpu)) audit(AUDIT_UNKNOWN_ARCH);
if ('x86_64' >!< cpu && cpu !~ "^i[3-6]86$" && 'aarch64' >!< cpu) audit(AUDIT_LOCAL_CHECKS_NOT_IMPLEMENTED, 'Debian', cpu);
var pkgs = [
{'release': '10.0', 'prefix': 'libnss3', 'reference': '2:3.42.1-1+deb10u7'},
{'release': '10.0', 'prefix': 'libnss3-dev', 'reference': '2:3.42.1-1+deb10u7'},
{'release': '10.0', 'prefix': 'libnss3-tools', 'reference': '2:3.42.1-1+deb10u7'}
];
var flag = 0;
foreach package_array ( pkgs ) {
var _release = NULL;
var prefix = NULL;
var reference = NULL;
if (!empty_or_null(package_array['release'])) _release = package_array['release'];
if (!empty_or_null(package_array['prefix'])) prefix = package_array['prefix'];
if (!empty_or_null(package_array['reference'])) reference = package_array['reference'];
if (_release && prefix && reference) {
if (deb_check(release:_release, prefix:prefix, reference:reference)) flag++;
}
}
if (flag)
{
security_report_v4(
port : 0,
severity : SECURITY_WARNING,
extra : deb_report_get()
);
exit(0);
}
else
{
var tested = deb_pkg_tests_get();
if (tested) audit(AUDIT_PACKAGE_NOT_AFFECTED, tested);
else audit(AUDIT_PACKAGE_NOT_INSTALLED, 'libnss3 / libnss3-dev / libnss3-tools');
}
cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2020-25648
cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2023-4421
packages.debian.org/source/buster/nss
security-tracker.debian.org/tracker/CVE-2020-25648
security-tracker.debian.org/tracker/CVE-2023-4421
security-tracker.debian.org/tracker/source-package/nss
www.debian.org/lts/security/2023/dla-3634
CVSS2
Attack Vector
NETWORK
Attack Complexity
LOW
Authentication
NONE
Confidentiality Impact
NONE
Integrity Impact
NONE
Availability Impact
PARTIAL
AV:N/AC:L/Au:N/C:N/I:N/A:P
CVSS3
Attack Vector
NETWORK
Attack Complexity
LOW
Privileges Required
NONE
User Interaction
NONE
Scope
UNCHANGED
Confidentiality Impact
NONE
Integrity Impact
NONE
Availability Impact
HIGH
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
AI Score
Confidence
High
EPSS
Percentile
82.1%