5.3 Medium
CVSS3
Attack Vector
NETWORK
Attack Complexity
LOW
Privileges Required
NONE
User Interaction
NONE
Scope
UNCHANGED
Confidentiality Impact
NONE
Integrity Impact
NONE
Availability Impact
LOW
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L
6.8 Medium
AI Score
Confidence
Low
0.001 Low
EPSS
Percentile
35.1%
The remote CentOS Linux 8 host has packages installed that are affected by multiple vulnerabilities as referenced in the CESA-2024:3233 advisory.
A flaw was found in libssh. By utilizing the ProxyCommand or ProxyJump feature, users can exploit unchecked hostname syntax on the client. This issue may allow an attacker to inject malicious code into the command of the features mentioned through the hostname parameter. (CVE-2023-6004)
A flaw was found in the libssh implements abstract layer for message digest (MD) operations implemented by different supported crypto backends. The return values from these were not properly checked, which could cause low-memory situations failures, NULL dereferences, crashes, or usage of the uninitialized memory as an input for the KDF. In this case, non-matching keys will result in decryption/integrity failures, terminating the connection. (CVE-2023-6918)
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 package checks in this plugin were extracted from
# Red Hat Security Advisory RHSA-2024:3233. The text
# itself is copyright (C) Red Hat, Inc.
##
include('compat.inc');
if (description)
{
script_id(197683);
script_version("1.0");
script_set_attribute(attribute:"plugin_modification_date", value:"2024/05/22");
script_cve_id("CVE-2023-6004", "CVE-2023-6918");
script_xref(name:"IAVA", value:"2023-A-0703");
script_xref(name:"RHSA", value:"2024:3233");
script_name(english:"CentOS 8 : libssh (CESA-2024:3233)");
script_set_attribute(attribute:"synopsis", value:
"The remote CentOS host is missing one or more security updates.");
script_set_attribute(attribute:"description", value:
"The remote CentOS Linux 8 host has packages installed that are affected by multiple vulnerabilities as referenced in the
CESA-2024:3233 advisory.
- A flaw was found in libssh. By utilizing the ProxyCommand or ProxyJump feature, users can exploit
unchecked hostname syntax on the client. This issue may allow an attacker to inject malicious code into
the command of the features mentioned through the hostname parameter. (CVE-2023-6004)
- A flaw was found in the libssh implements abstract layer for message digest (MD) operations implemented by
different supported crypto backends. The return values from these were not properly checked, which could
cause low-memory situations failures, NULL dereferences, crashes, or usage of the uninitialized memory as
an input for the KDF. In this case, non-matching keys will result in decryption/integrity failures,
terminating the connection. (CVE-2023-6918)
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://access.redhat.com/errata/RHSA-2024:3233");
script_set_attribute(attribute:"solution", value:
"Update the affected libssh, libssh-config and / or libssh-devel packages.");
script_set_cvss_base_vector("CVSS2#AV:L/AC:L/Au:S/C:P/I:P/A:P");
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:L/UI:R/S:U/C:L/I:L/A:L");
script_set_cvss3_temporal_vector("CVSS:3.0/E:U/RL:O/RC:C");
script_set_attribute(attribute:"cvss_score_source", value:"CVE-2023-6004");
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:"2023/12/19");
script_set_attribute(attribute:"patch_publication_date", value:"2024/05/22");
script_set_attribute(attribute:"plugin_publication_date", value:"2024/05/22");
script_set_attribute(attribute:"plugin_type", value:"local");
script_set_attribute(attribute:"cpe", value:"cpe:/o:centos:centos:8-stream");
script_set_attribute(attribute:"cpe", value:"p-cpe:/a:centos:centos:libssh");
script_set_attribute(attribute:"cpe", value:"p-cpe:/a:centos:centos:libssh-config");
script_set_attribute(attribute:"cpe", value:"p-cpe:/a:centos:centos:libssh-devel");
script_set_attribute(attribute:"generated_plugin", value:"current");
script_set_attribute(attribute:"stig_severity", value:"II");
script_end_attributes();
script_category(ACT_GATHER_INFO);
script_family(english:"CentOS 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/CentOS/release", "Host/CentOS/rpm-list", "Host/cpu");
exit(0);
}
include('rpm.inc');
include('rhel.inc');
if (!get_kb_item('Host/local_checks_enabled')) audit(AUDIT_LOCAL_CHECKS_NOT_ENABLED);
var os_release = get_kb_item('Host/CentOS/release');
if (isnull(os_release) || 'CentOS' >!< os_release) audit(AUDIT_OS_NOT, 'CentOS');
var os_ver = pregmatch(pattern: "CentOS(?: Stream)?(?: Linux)? release ([0-9]+)", string:os_release);
if (isnull(os_ver)) audit(AUDIT_UNKNOWN_APP_VER, 'CentOS');
os_ver = os_ver[1];
if ('CentOS Stream' >!< os_release) audit(AUDIT_OS_NOT, 'CentOS 8-Stream');
if (!rhel_check_release(operator: 'ge', os_version: os_ver, rhel_version: '8')) audit(AUDIT_OS_NOT, 'CentOS 8.x', 'CentOS ' + os_ver);
if (!get_kb_item('Host/CentOS/rpm-list')) 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 && 'ppc' >!< cpu) audit(AUDIT_LOCAL_CHECKS_NOT_IMPLEMENTED, 'CentOS', cpu);
var pkgs = [
{'reference':'libssh-0.9.6-14.el8', 'cpu':'aarch64', 'release':'8', 'rpm_spec_vers_cmp':TRUE},
{'reference':'libssh-0.9.6-14.el8', 'cpu':'x86_64', 'release':'8', 'rpm_spec_vers_cmp':TRUE},
{'reference':'libssh-config-0.9.6-14.el8', 'cpu':'aarch64', 'release':'8', 'rpm_spec_vers_cmp':TRUE},
{'reference':'libssh-config-0.9.6-14.el8', 'cpu':'x86_64', 'release':'8', 'rpm_spec_vers_cmp':TRUE},
{'reference':'libssh-devel-0.9.6-14.el8', 'cpu':'aarch64', 'release':'8', 'rpm_spec_vers_cmp':TRUE},
{'reference':'libssh-devel-0.9.6-14.el8', 'cpu':'x86_64', 'release':'8', 'rpm_spec_vers_cmp':TRUE}
];
var flag = 0;
foreach var package_array ( pkgs ) {
var reference = NULL;
var _release = NULL;
var sp = NULL;
var _cpu = NULL;
var el_string = NULL;
var rpm_spec_vers_cmp = NULL;
var epoch = NULL;
var allowmaj = NULL;
if (!empty_or_null(package_array['reference'])) reference = package_array['reference'];
if (!empty_or_null(package_array['release'])) _release = 'CentOS-' + package_array['release'];
if (!empty_or_null(package_array['sp'])) sp = package_array['sp'];
if (!empty_or_null(package_array['cpu'])) _cpu = package_array['cpu'];
if (!empty_or_null(package_array['el_string'])) el_string = package_array['el_string'];
if (!empty_or_null(package_array['rpm_spec_vers_cmp'])) rpm_spec_vers_cmp = package_array['rpm_spec_vers_cmp'];
if (!empty_or_null(package_array['epoch'])) epoch = package_array['epoch'];
if (!empty_or_null(package_array['allowmaj'])) allowmaj = package_array['allowmaj'];
if (reference && _release) {
if (rpm_check(release:_release, sp:sp, cpu:_cpu, reference:reference, epoch:epoch, el_string:el_string, rpm_spec_vers_cmp:rpm_spec_vers_cmp, allowmaj:allowmaj)) flag++;
}
}
if (flag)
{
security_report_v4(
port : 0,
severity : SECURITY_WARNING,
extra : rpm_report_get()
);
exit(0);
}
else
{
var tested = pkg_tests_get();
if (tested) audit(AUDIT_PACKAGE_NOT_AFFECTED, tested);
else audit(AUDIT_PACKAGE_NOT_INSTALLED, 'libssh / libssh-config / libssh-devel');
}
5.3 Medium
CVSS3
Attack Vector
NETWORK
Attack Complexity
LOW
Privileges Required
NONE
User Interaction
NONE
Scope
UNCHANGED
Confidentiality Impact
NONE
Integrity Impact
NONE
Availability Impact
LOW
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L
6.8 Medium
AI Score
Confidence
Low
0.001 Low
EPSS
Percentile
35.1%