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
Low
EPSS
Percentile
93.0%
The remote Debian 12 host has packages installed that are affected by multiple vulnerabilities as referenced in the dsa-5633 advisory.
Knot Resolver before 5.7.0 performs many TCP reconnections upon receiving certain nonsensical responses from servers. (CVE-2023-46317)
Certain DNSSEC aspects of the DNS protocol (in RFC 4033, 4034, 4035, 6840, and related RFCs) allow remote attackers to cause a denial of service (CPU consumption) via one or more DNSSEC responses, aka the KeyTrap issue. One of the concerns is that, when there is a zone with many DNSKEY and RRSIG records, the protocol specification implies that an algorithm must evaluate all combinations of DNSKEY and RRSIG records. (CVE-2023-50387)
The Closest Encloser Proof aspect of the DNS protocol (in RFC 5155 when RFC 9276 guidance is skipped) allows remote attackers to cause a denial of service (CPU consumption for SHA-1 computations) via DNSSEC responses in a random subdomain attack, aka the NSEC3 issue. The RFC 5155 specification implies that an algorithm must perform thousands of iterations of a hash function in certain situations. (CVE-2023-50868)
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 dsa-5633. The text
# itself is copyright (C) Software in the Public Interest, Inc.
#
include('compat.inc');
if (description)
{
script_id(191074);
script_version("1.0");
script_set_attribute(attribute:"plugin_modification_date", value:"2024/02/28");
script_cve_id("CVE-2023-46317", "CVE-2023-50387", "CVE-2023-50868");
script_name(english:"Debian dsa-5633 : knot-resolver - 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 12 host has packages installed that are affected by multiple vulnerabilities as referenced in the
dsa-5633 advisory.
- Knot Resolver before 5.7.0 performs many TCP reconnections upon receiving certain nonsensical responses
from servers. (CVE-2023-46317)
- Certain DNSSEC aspects of the DNS protocol (in RFC 4033, 4034, 4035, 6840, and related RFCs) allow remote
attackers to cause a denial of service (CPU consumption) via one or more DNSSEC responses, aka the
KeyTrap issue. One of the concerns is that, when there is a zone with many DNSKEY and RRSIG records, the
protocol specification implies that an algorithm must evaluate all combinations of DNSKEY and RRSIG
records. (CVE-2023-50387)
- The Closest Encloser Proof aspect of the DNS protocol (in RFC 5155 when RFC 9276 guidance is skipped)
allows remote attackers to cause a denial of service (CPU consumption for SHA-1 computations) via DNSSEC
responses in a random subdomain attack, aka the NSEC3 issue. The RFC 5155 specification implies that an
algorithm must perform thousands of iterations of a hash function in certain situations. (CVE-2023-50868)
Note that Nessus has not tested for these issues but has instead relied only on the application's self-reported version
number.");
# https://security-tracker.debian.org/tracker/source-package/knot-resolver
script_set_attribute(attribute:"see_also", value:"http://www.nessus.org/u?8a867234");
script_set_attribute(attribute:"see_also", value:"https://security-tracker.debian.org/tracker/CVE-2023-46317");
script_set_attribute(attribute:"see_also", value:"https://security-tracker.debian.org/tracker/CVE-2023-50387");
script_set_attribute(attribute:"see_also", value:"https://security-tracker.debian.org/tracker/CVE-2023-50868");
script_set_attribute(attribute:"see_also", value:"https://packages.debian.org/source/bookworm/knot-resolver");
script_set_attribute(attribute:"solution", value:
"Upgrade the knot-resolver packages.");
script_set_cvss_base_vector("CVSS2#AV:N/AC:L/Au:N/C:N/I:N/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:N/I:N/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-2023-50387");
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:"2023/10/22");
script_set_attribute(attribute:"patch_publication_date", value:"2024/02/27");
script_set_attribute(attribute:"plugin_publication_date", value:"2024/02/28");
script_set_attribute(attribute:"plugin_type", value:"local");
script_set_attribute(attribute:"cpe", value:"p-cpe:/a:debian:debian_linux:knot-resolver");
script_set_attribute(attribute:"cpe", value:"p-cpe:/a:debian:debian_linux:knot-resolver-doc");
script_set_attribute(attribute:"cpe", value:"p-cpe:/a:debian:debian_linux:knot-resolver-module-http");
script_set_attribute(attribute:"cpe", value:"cpe:/o:debian:debian_linux:12.0");
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) 2024 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:"^(12)\.[0-9]+", string:debian_release)) audit(AUDIT_OS_NOT, 'Debian 12.0', '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': '12.0', 'prefix': 'knot-resolver', 'reference': '5.6.0-1+deb12u1'},
{'release': '12.0', 'prefix': 'knot-resolver-doc', 'reference': '5.6.0-1+deb12u1'},
{'release': '12.0', 'prefix': 'knot-resolver-module-http', 'reference': '5.6.0-1+deb12u1'}
];
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_HOLE,
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, 'knot-resolver / knot-resolver-doc / knot-resolver-module-http');
}
cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2023-46317
cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2023-50387
cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2023-50868
www.nessus.org/u?8a867234
packages.debian.org/source/bookworm/knot-resolver
security-tracker.debian.org/tracker/CVE-2023-46317
security-tracker.debian.org/tracker/CVE-2023-50387
security-tracker.debian.org/tracker/CVE-2023-50868
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
Low
EPSS
Percentile
93.0%