Oracle Linux 9 : nginx:1.24 (ELSA-2026-6923)

#%NASL_MIN_LEVEL 80900
##
# (C) Tenable, Inc.
#
# The descriptive text and package checks in this plugin were
# extracted from Oracle Linux Security Advisory ELSA-2026-6923.
##

include('compat.inc');

if (description)
{
  script_id(305646);
  script_version("1.3");
  script_set_attribute(attribute:"plugin_modification_date", value:"2026/05/07");

  script_cve_id(
    "CVE-2026-27651",
    "CVE-2026-27654",
    "CVE-2026-27784",
    "CVE-2026-32647"
  );
  script_xref(name:"IAVA", value:"2026-A-0280");

  script_name(english:"Oracle Linux 9 : nginx:1.24 (ELSA-2026-6923)");

  script_set_attribute(attribute:"synopsis", value:
"The remote Oracle Linux host is missing one or more security updates.");
  script_set_attribute(attribute:"description", value:
"The remote Oracle Linux 9 host has packages installed that are affected by multiple vulnerabilities as referenced in the
ELSA-2026-6923 advisory.

    - Resolves: RHEL-157886 CVE-2026-32647 nginx:1.24/nginx: NGINX: Denial of
      Service or Code Execution via specially crafted MP4 files
    - Resolves: RHEL-159445 CVE-2026-27651 nginx:1.24/nginx: NGINX: Denial of
      Service via undisclosed requests when ngx_mail_auth_http_module is enabled
    - Resolves: RHEL-159558 CVE-2026-27654 nginx:1.24/nginx: NGINX: Denial of
      Service or file modification via buffer overflow in ngx_http_dav_module
    - Resolves: RHEL-159537 CVE-2026-27784 nginx:1.24/nginx: NGINX: Denial of
      Service due to memory corruption via crafted MP4 file
    - Resolves: RHEL-146526 - nginx:1.24/nginx: NGINX: Data injection via
      man-in-the-middle attack on TLS proxied connections (CVE-2026-1642)
    - Resolves: RHEL-84480 - nginx:1.24/nginx: specially crafted MP4 file may cause
      denial of service (CVE-2024-7347)

Tenable has extracted the preceding description block directly from the Oracle Linux 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://linux.oracle.com/errata/ELSA-2026-6923.html");
  script_set_attribute(attribute:"solution", value:
"Update the affected packages.");
  script_set_cvss_base_vector("CVSS2#AV:N/AC:L/Au:N/C:N/I:P/A:C");
  script_set_cvss_temporal_vector("CVSS2#E:POC/RL:OF/RC:C");
  script_set_cvss3_base_vector("CVSS:3.0/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H");
  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:L/AC:L/AT:N/PR:L/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-2026-27654");
  script_set_attribute(attribute:"cvss3_score_source", value:"CVE-2026-27784");
  script_set_attribute(attribute:"cvss4_score_source", value:"CVE-2026-27784");

  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:"2026/03/24");
  script_set_attribute(attribute:"patch_publication_date", value:"2026/04/08");
  script_set_attribute(attribute:"plugin_publication_date", value:"2026/04/08");

  script_set_attribute(attribute:"plugin_type", value:"local");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:oracle:linux:9");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:oracle:linux:nginx");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:oracle:linux:nginx-all-modules");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:oracle:linux:nginx-core");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:oracle:linux:nginx-filesystem");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:oracle:linux:nginx-mod-devel");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:oracle:linux:nginx-mod-http-image-filter");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:oracle:linux:nginx-mod-http-perl");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:oracle:linux:nginx-mod-http-xslt-filter");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:oracle:linux:nginx-mod-mail");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:oracle:linux:nginx-mod-stream");
  script_set_attribute(attribute:"generated_plugin", value:"current");
  script_set_attribute(attribute:"stig_severity", value:"I");
  script_end_attributes();

  script_category(ACT_GATHER_INFO);
  script_family(english:"Oracle Linux Local Security Checks");

  script_copyright(english:"This script is Copyright (C) 2026 and is owned by Tenable, Inc. or an Affiliate thereof.");

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

  exit(0);
}


include('rpm2.inc');

if (!get_kb_item('Host/local_checks_enabled')) audit(AUDIT_LOCAL_CHECKS_NOT_ENABLED);
var os_product = get_kb_item('installed_os/local/SSH/0/product');
if (isnull(os_product) || !pregmatch(pattern: "Oracle (?:Linux Server|Enterprise Linux)", string:os_product)) audit(AUDIT_OS_NOT, 'Oracle Linux');
var os_version = get_kb_item('installed_os/local/SSH/0/version');
if (isnull(os_version)) audit(AUDIT_UNKNOWN_APP_VER, 'Oracle Linux');
if (! preg(pattern:"^9([^0-9]|$)", string:os_version)) audit(AUDIT_OS_NOT, 'Oracle Linux 9.x', 'Oracle Linux ' + os_version);

if (!get_kb_item('Host/RedHat/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$" && 'aarch64' >!< cpu) audit(AUDIT_LOCAL_CHECKS_NOT_IMPLEMENTED, 'Oracle Linux', cpu);

var module_ver = get_kb_item('Host/RedHat/appstream/nginx');
if (isnull(module_ver)) audit(AUDIT_PACKAGE_NOT_INSTALLED, 'Module nginx:1.24');
if ('1.24' >!< module_ver) audit(AUDIT_PACKAGE_NOT_AFFECTED, 'Module nginx:' + module_ver);

var constraints = {
  'nginx:1.24': [
    {
      'release': '9',
      'pkgs': [
        {'reference':'nginx-1.24.0-5.0.1.module+el9.7.0+90864+a04e5d5f.2', 'cpu':'aarch64', 'rpm_spec_vers_cmp':TRUE, 'epoch':'1'},
        {'reference':'nginx-all-modules-1.24.0-5.0.1.module+el9.7.0+90864+a04e5d5f.2', 'cpu':'aarch64', 'rpm_spec_vers_cmp':TRUE, 'epoch':'1'},
        {'reference':'nginx-core-1.24.0-5.0.1.module+el9.7.0+90864+a04e5d5f.2', 'cpu':'aarch64', 'rpm_spec_vers_cmp':TRUE, 'epoch':'1'},
        {'reference':'nginx-filesystem-1.24.0-5.0.1.module+el9.7.0+90864+a04e5d5f.2', 'cpu':'aarch64', 'rpm_spec_vers_cmp':TRUE, 'epoch':'1'},
        {'reference':'nginx-mod-devel-1.24.0-5.0.1.module+el9.7.0+90864+a04e5d5f.2', 'cpu':'aarch64', 'rpm_spec_vers_cmp':TRUE, 'epoch':'1'},
        {'reference':'nginx-mod-http-image-filter-1.24.0-5.0.1.module+el9.7.0+90864+a04e5d5f.2', 'cpu':'aarch64', 'rpm_spec_vers_cmp':TRUE, 'epoch':'1'},
        {'reference':'nginx-mod-http-perl-1.24.0-5.0.1.module+el9.7.0+90864+a04e5d5f.2', 'cpu':'aarch64', 'rpm_spec_vers_cmp':TRUE, 'epoch':'1'},
        {'reference':'nginx-mod-http-xslt-filter-1.24.0-5.0.1.module+el9.7.0+90864+a04e5d5f.2', 'cpu':'aarch64', 'rpm_spec_vers_cmp':TRUE, 'epoch':'1'},
        {'reference':'nginx-mod-mail-1.24.0-5.0.1.module+el9.7.0+90864+a04e5d5f.2', 'cpu':'aarch64', 'rpm_spec_vers_cmp':TRUE, 'epoch':'1'},
        {'reference':'nginx-mod-stream-1.24.0-5.0.1.module+el9.7.0+90864+a04e5d5f.2', 'cpu':'aarch64', 'rpm_spec_vers_cmp':TRUE, 'epoch':'1'},
        {'reference':'nginx-1.24.0-5.0.1.module+el9.7.0+90864+a04e5d5f.2', 'cpu':'x86_64', 'rpm_spec_vers_cmp':TRUE, 'epoch':'1'},
        {'reference':'nginx-all-modules-1.24.0-5.0.1.module+el9.7.0+90864+a04e5d5f.2', 'cpu':'x86_64', 'rpm_spec_vers_cmp':TRUE, 'epoch':'1'},
        {'reference':'nginx-core-1.24.0-5.0.1.module+el9.7.0+90864+a04e5d5f.2', 'cpu':'x86_64', 'rpm_spec_vers_cmp':TRUE, 'epoch':'1'},
        {'reference':'nginx-filesystem-1.24.0-5.0.1.module+el9.7.0+90864+a04e5d5f.2', 'cpu':'x86_64', 'rpm_spec_vers_cmp':TRUE, 'epoch':'1'},
        {'reference':'nginx-mod-devel-1.24.0-5.0.1.module+el9.7.0+90864+a04e5d5f.2', 'cpu':'x86_64', 'rpm_spec_vers_cmp':TRUE, 'epoch':'1'},
        {'reference':'nginx-mod-http-image-filter-1.24.0-5.0.1.module+el9.7.0+90864+a04e5d5f.2', 'cpu':'x86_64', 'rpm_spec_vers_cmp':TRUE, 'epoch':'1'},
        {'reference':'nginx-mod-http-perl-1.24.0-5.0.1.module+el9.7.0+90864+a04e5d5f.2', 'cpu':'x86_64', 'rpm_spec_vers_cmp':TRUE, 'epoch':'1'},
        {'reference':'nginx-mod-http-xslt-filter-1.24.0-5.0.1.module+el9.7.0+90864+a04e5d5f.2', 'cpu':'x86_64', 'rpm_spec_vers_cmp':TRUE, 'epoch':'1'},
        {'reference':'nginx-mod-mail-1.24.0-5.0.1.module+el9.7.0+90864+a04e5d5f.2', 'cpu':'x86_64', 'rpm_spec_vers_cmp':TRUE, 'epoch':'1'},
        {'reference':'nginx-mod-stream-1.24.0-5.0.1.module+el9.7.0+90864+a04e5d5f.2', 'cpu':'x86_64', 'rpm_spec_vers_cmp':TRUE, 'epoch':'1'}
      ]
    }
  ]
};

var os_release = get_one_kb_item('installed_os/local/SSH/0/release');
var os_sp = get_one_kb_item('Host/*/minor_release');

var flag = 0;
var reference;
var sp;
var _cpu;
var el_string;
var rpm_spec_vers_cmp;
var epoch;
var allowmaj;
var exists_check;
var cves;
var appstreams_found = 0;
var appstream;
var appstream_name;
var appstream_version;
foreach var module (keys(constraints)) {
  appstream = NULL;
  appstream_name = NULL;
  appstream_version = NULL;
  appstream_split = split(module, sep:':', keep:FALSE);
  if (!empty_or_null(appstream_split)) {
    appstream_name = appstream_split[0];
    appstream_version = appstream_split[1];
    if (!empty_or_null(appstream_name)) appstream = get_one_kb_item('Host/RedHat/appstream/' + appstream_name);
  }
  if (!empty_or_null(appstream) && appstream_version == appstream || appstream_name == 'all') {
    appstreams_found++;
    foreach var module_array ( constraints[module] ) {
      # Check that the target release is equal to the affected release
      if (!empty_or_null(module_array['release'])){
        if (module_array['release'] != os_release) continue;
      }
      if (!empty_or_null(module_array['sp'])){
        if (module_array['sp'] != os_sp) continue;
      }
      foreach var package_array ( module_array['pkgs'] ) {
        reference = NULL;
        sp = NULL;
        _cpu = NULL;
        el_string = NULL;
        rpm_spec_vers_cmp = NULL;
        epoch = NULL;
        allowmaj = NULL;
        exists_check = NULL;
        cves = NULL;
        if (!empty_or_null(package_array['reference'])) reference = package_array['reference'];
        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 &&
            (!exists_check || rpm_exists(rpm:exists_check)) &&
            rpm_check(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 (!appstreams_found) audit(AUDIT_PACKAGE_NOT_INSTALLED, 'Module nginx:1.24');

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, 'nginx / nginx-all-modules / nginx-core / etc');
}