Amazon Linux 2023 : libssh, libssh-config, libssh-devel (ALAS2023-2023-186)

#%NASL_MIN_LEVEL 80900
##
# (C) Tenable, Inc.
#
# The descriptive text and package checks in this plugin were
# extracted from Amazon Linux 2023 Security Advisory ALAS2023-2023-186.
##

include('compat.inc');

if (description)
{
  script_id(176977);
  script_version("1.4");
  script_set_attribute(attribute:"plugin_modification_date", value:"2024/12/11");

  script_cve_id("CVE-2023-1667", "CVE-2023-2283");
  script_xref(name:"IAVA", value:"2023-A-0517-S");

  script_name(english:"Amazon Linux 2023 : libssh, libssh-config, libssh-devel (ALAS2023-2023-186)");

  script_set_attribute(attribute:"synopsis", value:
"The remote Amazon Linux 2023 host is missing a security update.");
  script_set_attribute(attribute:"description", value:
"It is, therefore, affected by multiple vulnerabilities as referenced in the ALAS2023-2023-186 advisory.

    A NULL pointer dereference was found In libssh during re-keying with algorithm guessing. This issue may
    allow an authenticated client to cause a denial of service. (CVE-2023-1667)

    A vulnerability was found in libssh, where the authentication check of the connecting client can be
    bypassed in thepki_verify_data_signature function in memory allocation problems. This issue may happen if
    there is insufficient memory or the memory usage is limited. The problem is caused by the return value rc,
    which is initialized to SSH_ERROR and later rewritten to save the return value of the function call
    pki_key_check_hash_compatible. The value of the variable is not changed between this point and the
    cryptographic verification. Therefore any error between them calls goto error returning SSH_OK.
    (CVE-2023-2283)

Tenable has extracted the preceding description block directly from the tested product security advisory.

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://alas.aws.amazon.com/AL2023/ALAS-2023-186.html");
  script_set_attribute(attribute:"see_also", value:"https://alas.aws.amazon.com/cve/html/CVE-2023-1667.html");
  script_set_attribute(attribute:"see_also", value:"https://alas.aws.amazon.com/cve/html/CVE-2023-2283.html");
  script_set_attribute(attribute:"see_also", value:"https://alas.aws.amazon.com/faqs.html");
  script_set_attribute(attribute:"solution", value:
"Run 'dnf update libssh --releasever 2023.0.20230607' to update your system.");
  script_set_cvss_base_vector("CVSS2#AV:N/AC:L/Au:N/C:P/I:P/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:L/PR:N/UI:N/S:U/C:L/I:L/A:N");
  script_set_cvss3_temporal_vector("CVSS:3.0/E:P/RL:O/RC:C");
  script_set_attribute(attribute:"cvss_score_source", value:"CVE-2023-2283");

  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:"2023/05/11");
  script_set_attribute(attribute:"patch_publication_date", value:"2023/05/25");
  script_set_attribute(attribute:"plugin_publication_date", value:"2023/06/08");

  script_set_attribute(attribute:"plugin_type", value:"local");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:amazon:linux:libssh");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:amazon:linux:libssh-config");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:amazon:linux:libssh-debuginfo");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:amazon:linux:libssh-debugsource");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:amazon:linux:libssh-devel");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:amazon:linux:2023");
  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:"Amazon Linux Local Security Checks");

  script_copyright(english:"This script is Copyright (C) 2023-2024 and is owned by Tenable, Inc. or an Affiliate thereof.");

  script_dependencies("ssh_get_info.nasl");
  script_require_keys("Host/local_checks_enabled", "Host/AmazonLinux/release", "Host/AmazonLinux/rpm-list");

  exit(0);
}

include("rpm.inc");

if (!get_kb_item("Host/local_checks_enabled")) audit(AUDIT_LOCAL_CHECKS_NOT_ENABLED);

var alas_release = get_kb_item("Host/AmazonLinux/release");
if (isnull(alas_release) || !strlen(alas_release)) audit(AUDIT_OS_NOT, "Amazon Linux");
var os_ver = pregmatch(pattern: "^AL(A|\d+|-\d+)", string:alas_release);
if (isnull(os_ver)) audit(AUDIT_UNKNOWN_APP_VER, "Amazon Linux");
os_ver = os_ver[1];
if (os_ver != "-2023")
{
  if (os_ver == 'A') os_ver = 'AMI';
  audit(AUDIT_OS_NOT, "Amazon Linux 2023", "Amazon Linux " + os_ver);
}

if (!get_kb_item("Host/AmazonLinux/rpm-list")) audit(AUDIT_PACKAGE_LIST_MISSING);

var pkgs = [
    {'reference':'libssh-0.10.5-1.amzn2023.0.1', 'cpu':'aarch64', 'release':'AL-2023', 'rpm_spec_vers_cmp':TRUE},
    {'reference':'libssh-0.10.5-1.amzn2023.0.1', 'cpu':'i686', 'release':'AL-2023', 'rpm_spec_vers_cmp':TRUE},
    {'reference':'libssh-0.10.5-1.amzn2023.0.1', 'cpu':'x86_64', 'release':'AL-2023', 'rpm_spec_vers_cmp':TRUE},
    {'reference':'libssh-config-0.10.5-1.amzn2023.0.1', 'release':'AL-2023', 'rpm_spec_vers_cmp':TRUE},
    {'reference':'libssh-debuginfo-0.10.5-1.amzn2023.0.1', 'cpu':'aarch64', 'release':'AL-2023', 'rpm_spec_vers_cmp':TRUE},
    {'reference':'libssh-debuginfo-0.10.5-1.amzn2023.0.1', 'cpu':'i686', 'release':'AL-2023', 'rpm_spec_vers_cmp':TRUE},
    {'reference':'libssh-debuginfo-0.10.5-1.amzn2023.0.1', 'cpu':'x86_64', 'release':'AL-2023', 'rpm_spec_vers_cmp':TRUE},
    {'reference':'libssh-debugsource-0.10.5-1.amzn2023.0.1', 'cpu':'aarch64', 'release':'AL-2023', 'rpm_spec_vers_cmp':TRUE},
    {'reference':'libssh-debugsource-0.10.5-1.amzn2023.0.1', 'cpu':'i686', 'release':'AL-2023', 'rpm_spec_vers_cmp':TRUE},
    {'reference':'libssh-debugsource-0.10.5-1.amzn2023.0.1', 'cpu':'x86_64', 'release':'AL-2023', 'rpm_spec_vers_cmp':TRUE},
    {'reference':'libssh-devel-0.10.5-1.amzn2023.0.1', 'cpu':'aarch64', 'release':'AL-2023', 'rpm_spec_vers_cmp':TRUE},
    {'reference':'libssh-devel-0.10.5-1.amzn2023.0.1', 'cpu':'i686', 'release':'AL-2023', 'rpm_spec_vers_cmp':TRUE},
    {'reference':'libssh-devel-0.10.5-1.amzn2023.0.1', 'cpu':'x86_64', 'release':'AL-2023', '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;
  var exists_check = NULL;
  var cves = NULL;
  if (!empty_or_null(package_array['reference'])) reference = package_array['reference'];
  if (!empty_or_null(package_array['release'])) _release = 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 (!empty_or_null(package_array['exists_check'])) exists_check = package_array['exists_check'];
  if (!empty_or_null(package_array['cves'])) cves = package_array['cves'];
  if (reference && _release && (!exists_check || rpm_exists(release:_release, rpm:exists_check))) {
    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, cves:cves)) 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-debuginfo / etc");
}