Rocky Linux 9 : OpenSSH regreSSHion (CVE-2024-6387)

#%NASL_MIN_LEVEL 80900
##
# (C) Tenable, Inc.
#
# The package checks in this plugin were extracted from
# Rocky Linux Security Advisory RLSA-2024:5138.
##

include('compat.inc');

if (description)
{
  script_id(206464);
  script_version("1.2");
  script_set_attribute(attribute:"plugin_modification_date", value:"2024/09/04");

  script_cve_id("CVE-2024-6387");

  script_name(english:"Rocky Linux 9 : OpenSSH regreSSHion (CVE-2024-6387)");

  script_set_attribute(attribute:"synopsis", value:
"The remote Rocky Linux host is missing a security update.");
  script_set_attribute(attribute:"description", value:
"The remote Rocky Linux 9 host has packages installed that are affected by a vulnerability as referenced in the
'Rocky Linux 9 - CVE-2024-6387: regreSSHion' news article.

    * sshd: Signal handler race condition that can lead to a potential remote code execution.
    (CVE-2024-6387)

Note this plugin only checks the base OpenSSH package. Nessus has not tested for this issue but has instead relied only 
on the application's self-reported version number. There are mitigations available which this plugin is unable to test 
for and there may also be other packages that need to be updated, but are not explicitly specified in the news article.");
  script_set_attribute(attribute:"see_also", value:"https://rockylinux.org/news/2024-07-01-openssh-sigalrm-regression");
  script_set_attribute(attribute:"see_also", value:"https://access.redhat.com/errata/RHSA-2024:4312");
  script_set_attribute(attribute:"see_also", value:"https://bugzilla.redhat.com/show_bug.cgi?id=2294604");
  script_set_attribute(attribute:"solution", value:
"Update the affected packages as per the vendor documentation.");
  script_set_cvss_base_vector("CVSS2#AV:N/AC:H/Au:N/C:C/I:C/A:C");
  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:H/I:H/A:H");
  script_set_cvss3_temporal_vector("CVSS:3.0/E:P/RL:O/RC:C");
  script_set_attribute(attribute:"cvss_score_source", value:"CVE-2024-6387");

  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:"2024/06/26");
  script_set_attribute(attribute:"patch_publication_date", value:"2024/07/03");
  script_set_attribute(attribute:"plugin_publication_date", value:"2024/09/03");

  script_set_attribute(attribute:"plugin_type", value:"local");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:rocky:linux:openssh");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:rocky:linux:9");
  script_end_attributes();

  script_category(ACT_GATHER_INFO);
  script_family(english:"Rocky Linux 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/RockyLinux/release", "Host/RockyLinux/rpm-list", "Host/cpu");

  exit(0);
}


include('rpm.inc');

if (!get_kb_item('Host/local_checks_enabled')) audit(AUDIT_LOCAL_CHECKS_NOT_ENABLED);
var os_release = get_kb_item('Host/RockyLinux/release');
if (isnull(os_release) || 'Rocky Linux' >!< os_release) audit(AUDIT_OS_NOT, 'Rocky Linux');
var os_ver = pregmatch(pattern: "Rocky(?: Linux)? release ([0-9]+(\.[0-9]+)?)", string:os_release);
if (isnull(os_ver)) audit(AUDIT_UNKNOWN_APP_VER, 'Rocky Linux');
os_ver = os_ver[1];
if (! preg(pattern:"^9([^0-9]|$)", string:os_ver)) audit(AUDIT_OS_NOT, 'Rocky Linux 9.x', 'Rocky Linux ' + os_ver);

if (!get_kb_item('Host/RockyLinux/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) audit(AUDIT_LOCAL_CHECKS_NOT_IMPLEMENTED, 'Rocky Linux', cpu);

var pkgs = [
    {'reference':'openssh-8.7p1-38.el9_4.1', 'cpu':'aarch64', 'release':'9', 'rpm_spec_vers_cmp':TRUE},
    {'reference':'openssh-8.7p1-38.el9_4.1', 'cpu':'s390x', 'release':'9', 'rpm_spec_vers_cmp':TRUE},
    {'reference':'openssh-8.7p1-38.el9_4.1', 'cpu':'x86_64', 'release':'9', '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;
  if (!empty_or_null(package_array['reference'])) reference = package_array['reference'];
  if (!empty_or_null(package_array['release'])) _release = 'Rocky-' + 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 (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)) flag++;
  }
}

if (flag)
{
  security_report_v4(
      port       : 0,
      severity   : SECURITY_HOLE,
      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, 'openssh');
}