CVSS3
Attack Vector
NETWORK
Attack Complexity
HIGH
Privileges Required
NONE
User Interaction
NONE
Scope
UNCHANGED
Confidentiality Impact
NONE
Integrity Impact
HIGH
Availability Impact
NONE
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:H/A:N
AI Score
Confidence
High
EPSS
Percentile
99.6%
The remote Ubuntu 20.04 LTS / 22.04 LTS / 23.10 host has a package installed that is affected by a vulnerability as referenced in the USN-6598-1 advisory.
Fabian Bumer, Marcus Brinkmann, Jrg Schwenk discovered that the SSH protocol was vulnerable to a prefix truncation attack. If a remote attacker was able to intercept SSH communications, extension negotiation messages could be truncated, possibly leading to certain algorithms and features being downgraded. This issue is known as the Terrapin attack. This update adds protocol extensions to mitigate this issue.
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-6598-1. 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(189519);
script_version("1.3");
script_set_attribute(attribute:"plugin_modification_date", value:"2024/09/18");
script_cve_id("CVE-2023-48795");
script_xref(name:"USN", value:"6598-1");
script_name(english:"Ubuntu 20.04 LTS / 22.04 LTS / 23.10 : Paramiko vulnerability (USN-6598-1)");
script_set_attribute(attribute:"synopsis", value:
"The remote Ubuntu host is missing a security update.");
script_set_attribute(attribute:"description", value:
"The remote Ubuntu 20.04 LTS / 22.04 LTS / 23.10 host has a package installed that is affected by a vulnerability as
referenced in the USN-6598-1 advisory.
Fabian Bumer, Marcus Brinkmann, Jrg Schwenk discovered that the SSH protocol was vulnerable to a
prefix truncation attack. If a remote attacker was able to intercept SSH communications, extension
negotiation messages could be truncated, possibly leading to certain algorithms and features being
downgraded. This issue is known as the Terrapin attack. This update adds protocol extensions to mitigate
this issue.
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-6598-1");
script_set_attribute(attribute:"solution", value:
"Update the affected python3-paramiko package.");
script_set_cvss_base_vector("CVSS2#AV:N/AC:H/Au:N/C:N/I:C/A:N");
script_set_cvss_temporal_vector("CVSS2#E:POC/RL:OF/RC:C");
script_set_cvss3_base_vector("CVSS:3.0/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:H/A:N");
script_set_cvss3_temporal_vector("CVSS:3.0/E:P/RL:O/RC:C");
script_set_attribute(attribute:"cvss4_vector", value:"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N");
script_set_attribute(attribute:"cvss4_threat_vector", value:"CVSS:4.0/E:P");
script_set_attribute(attribute:"cvss_score_source", value:"CVE-2023-48795");
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:"2023/12/18");
script_set_attribute(attribute:"patch_publication_date", value:"2024/01/25");
script_set_attribute(attribute:"plugin_publication_date", value:"2024/01/25");
script_set_attribute(attribute:"plugin_type", value:"local");
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:"p-cpe:/a:canonical:ubuntu_linux:python3-paramiko");
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");
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 (! ('20.04' >< os_release || '22.04' >< os_release || '23.10' >< os_release)) audit(AUDIT_OS_NOT, 'Ubuntu 20.04 / 22.04 / 23.10', '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': '20.04', 'pkgname': 'python3-paramiko', 'pkgver': '2.6.0-2ubuntu0.3'},
{'osver': '22.04', 'pkgname': 'python3-paramiko', 'pkgver': '2.9.3-0ubuntu1.2'},
{'osver': '23.10', 'pkgname': 'python3-paramiko', 'pkgver': '2.12.0-2ubuntu1.23.10.2'}
];
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'];
if (osver && pkgname && pkgver) {
if (ubuntu_check(osver:osver, pkgname:pkgname, pkgver:pkgver)) flag++;
}
}
if (flag)
{
var extra = '';
extra += ubuntu_report_get();
security_report_v4(
port : 0,
severity : SECURITY_WARNING,
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, 'python3-paramiko');
}
CVSS3
Attack Vector
NETWORK
Attack Complexity
HIGH
Privileges Required
NONE
User Interaction
NONE
Scope
UNCHANGED
Confidentiality Impact
NONE
Integrity Impact
HIGH
Availability Impact
NONE
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:H/A:N
AI Score
Confidence
High
EPSS
Percentile
99.6%