Debian dla-4634 : libnginx-mod-http-auth-pam - security update

#%NASL_MIN_LEVEL 80900
#
# (C) Tenable, Inc.
#
# The descriptive text and package checks in this plugin were
# extracted from Debian Security Advisory dla-4634. The text
# itself is copyright (C) Software in the Public Interest, Inc.
#

include('compat.inc');

if (description)
{
  script_id(321720);
  script_version("1.1");
  script_set_attribute(attribute:"plugin_modification_date", value:"2026/06/20");

  script_cve_id("CVE-2026-9256");
  script_xref(name:"IAVA", value:"2026-A-0515");

  script_name(english:"Debian dla-4634 : libnginx-mod-http-auth-pam - security update");

  script_set_attribute(attribute:"synopsis", value:
"The remote Debian host is missing a security-related update.");
  script_set_attribute(attribute:"description", value:
"The remote Debian 11 host has packages installed that are affected by a vulnerability as referenced in the dla-4634
advisory.

    -------------------------------------------------------------------------
    Debian LTS Advisory DLA-4634-1                [email protected]
    https://www.debian.org/lts/security/          Carlos Henrique Lima Melara
    June 17, 2026                                 https://wiki.debian.org/LTS
    -------------------------------------------------------------------------

    Package        : nginx
    Version        : 1.18.0-6.1+deb11u7
    CVE ID         : CVE-2026-9256
    Debian Bug     : 1137339


    A vulnerability was discoverd in Nginx, a high-performance web and reverse
    proxy server, which could result in remote code execution and denial of
    service.

    For Debian 11 bullseye, this problem has been fixed in version
    1.18.0-6.1+deb11u7.

    We recommend that you upgrade your nginx packages.

    For the detailed security status of nginx please refer to
    its security tracker page at:
    https://security-tracker.debian.org/tracker/nginx

    Further information about Debian LTS security advisories, how to apply
    these updates to your system and frequently asked questions can be
    found at: https://wiki.debian.org/LTS
    Attachment:
    signature.asc
    Description: PGP signature

Tenable has extracted the preceding description block directly from the Debian 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://security-tracker.debian.org/tracker/source-package/nginx");
  script_set_attribute(attribute:"see_also", value:"https://security-tracker.debian.org/tracker/CVE-2026-9256");
  script_set_attribute(attribute:"see_also", value:"https://packages.debian.org/source/bullseye/nginx");
  script_set_attribute(attribute:"solution", value:
"Upgrade the libnginx-mod-http-auth-pam packages.");
  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:"cvss4_vector", value:"CVSS:4.0/AV:N/AC:H/AT:P/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-2026-9256");

  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:"2026/05/22");
  script_set_attribute(attribute:"patch_publication_date", value:"2026/06/17");
  script_set_attribute(attribute:"plugin_publication_date", value:"2026/06/20");

  script_set_attribute(attribute:"plugin_type", value:"local");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:debian:debian_linux:libnginx-mod-http-auth-pam");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:debian:debian_linux:libnginx-mod-http-cache-purge");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:debian:debian_linux:libnginx-mod-http-dav-ext");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:debian:debian_linux:libnginx-mod-http-echo");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:debian:debian_linux:libnginx-mod-http-fancyindex");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:debian:debian_linux:libnginx-mod-http-geoip");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:debian:debian_linux:libnginx-mod-http-geoip2");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:debian:debian_linux:libnginx-mod-http-headers-more-filter");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:debian:debian_linux:libnginx-mod-http-image-filter");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:debian:debian_linux:libnginx-mod-http-lua");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:debian:debian_linux:libnginx-mod-http-ndk");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:debian:debian_linux:libnginx-mod-http-perl");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:debian:debian_linux:libnginx-mod-http-subs-filter");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:debian:debian_linux:libnginx-mod-http-uploadprogress");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:debian:debian_linux:libnginx-mod-http-upstream-fair");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:debian:debian_linux:libnginx-mod-http-xslt-filter");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:debian:debian_linux:libnginx-mod-mail");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:debian:debian_linux:libnginx-mod-nchan");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:debian:debian_linux:libnginx-mod-rtmp");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:debian:debian_linux:libnginx-mod-stream");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:debian:debian_linux:libnginx-mod-stream-geoip");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:debian:debian_linux:libnginx-mod-stream-geoip2");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:debian:debian_linux:nginx");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:debian:debian_linux:nginx-common");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:debian:debian_linux:nginx-core");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:debian:debian_linux:nginx-doc");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:debian:debian_linux:nginx-extras");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:debian:debian_linux:nginx-full");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:debian:debian_linux:nginx-light");
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  script_set_attribute(attribute:"generated_plugin", value:"current");
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  script_category(ACT_GATHER_INFO);
  script_family(english:"Debian 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/local_checks_enabled", "Host/Debian/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);
if (!get_kb_item("Host/Debian/dpkg-l")) audit(AUDIT_PACKAGE_LIST_MISSING);

var debian_release = get_kb_item('Host/Debian/release');
if ( isnull(debian_release) ) audit(AUDIT_OS_NOT, 'Debian');
debian_release = chomp(debian_release);
if (! preg(pattern:"^(11)\.[0-9]+", string:debian_release)) audit(AUDIT_OS_NOT, 'Debian 11.0', 'Debian ' + debian_release);
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, 'Debian', cpu);

var pkgs = [
    {'release': '11.0', 'prefix': 'libnginx-mod-http-auth-pam', 'reference': '1.18.0-6.1+deb11u7'},
    {'release': '11.0', 'prefix': 'libnginx-mod-http-cache-purge', 'reference': '1.18.0-6.1+deb11u7'},
    {'release': '11.0', 'prefix': 'libnginx-mod-http-dav-ext', 'reference': '1.18.0-6.1+deb11u7'},
    {'release': '11.0', 'prefix': 'libnginx-mod-http-echo', 'reference': '1.18.0-6.1+deb11u7'},
    {'release': '11.0', 'prefix': 'libnginx-mod-http-fancyindex', 'reference': '1.18.0-6.1+deb11u7'},
    {'release': '11.0', 'prefix': 'libnginx-mod-http-geoip', 'reference': '1.18.0-6.1+deb11u7'},
    {'release': '11.0', 'prefix': 'libnginx-mod-http-geoip2', 'reference': '1.18.0-6.1+deb11u7'},
    {'release': '11.0', 'prefix': 'libnginx-mod-http-headers-more-filter', 'reference': '1.18.0-6.1+deb11u7'},
    {'release': '11.0', 'prefix': 'libnginx-mod-http-image-filter', 'reference': '1.18.0-6.1+deb11u7'},
    {'release': '11.0', 'prefix': 'libnginx-mod-http-lua', 'reference': '1.18.0-6.1+deb11u7'},
    {'release': '11.0', 'prefix': 'libnginx-mod-http-ndk', 'reference': '1.18.0-6.1+deb11u7'},
    {'release': '11.0', 'prefix': 'libnginx-mod-http-perl', 'reference': '1.18.0-6.1+deb11u7'},
    {'release': '11.0', 'prefix': 'libnginx-mod-http-subs-filter', 'reference': '1.18.0-6.1+deb11u7'},
    {'release': '11.0', 'prefix': 'libnginx-mod-http-uploadprogress', 'reference': '1.18.0-6.1+deb11u7'},
    {'release': '11.0', 'prefix': 'libnginx-mod-http-upstream-fair', 'reference': '1.18.0-6.1+deb11u7'},
    {'release': '11.0', 'prefix': 'libnginx-mod-http-xslt-filter', 'reference': '1.18.0-6.1+deb11u7'},
    {'release': '11.0', 'prefix': 'libnginx-mod-mail', 'reference': '1.18.0-6.1+deb11u7'},
    {'release': '11.0', 'prefix': 'libnginx-mod-nchan', 'reference': '1.18.0-6.1+deb11u7'},
    {'release': '11.0', 'prefix': 'libnginx-mod-rtmp', 'reference': '1.18.0-6.1+deb11u7'},
    {'release': '11.0', 'prefix': 'libnginx-mod-stream', 'reference': '1.18.0-6.1+deb11u7'},
    {'release': '11.0', 'prefix': 'libnginx-mod-stream-geoip', 'reference': '1.18.0-6.1+deb11u7'},
    {'release': '11.0', 'prefix': 'libnginx-mod-stream-geoip2', 'reference': '1.18.0-6.1+deb11u7'},
    {'release': '11.0', 'prefix': 'nginx', 'reference': '1.18.0-6.1+deb11u7'},
    {'release': '11.0', 'prefix': 'nginx-common', 'reference': '1.18.0-6.1+deb11u7'},
    {'release': '11.0', 'prefix': 'nginx-core', 'reference': '1.18.0-6.1+deb11u7'},
    {'release': '11.0', 'prefix': 'nginx-doc', 'reference': '1.18.0-6.1+deb11u7'},
    {'release': '11.0', 'prefix': 'nginx-extras', 'reference': '1.18.0-6.1+deb11u7'},
    {'release': '11.0', 'prefix': 'nginx-full', 'reference': '1.18.0-6.1+deb11u7'},
    {'release': '11.0', 'prefix': 'nginx-light', 'reference': '1.18.0-6.1+deb11u7'}
];

var flag = 0;
foreach package_array ( pkgs ) {
  var _release = NULL;
  var prefix = NULL;
  var reference = NULL;
  if (!empty_or_null(package_array['release'])) _release = package_array['release'];
  if (!empty_or_null(package_array['prefix'])) prefix = package_array['prefix'];
  if (!empty_or_null(package_array['reference'])) reference = package_array['reference'];
  if (_release && prefix && reference) {
    if (deb_check(release:_release, prefix:prefix, reference:reference)) flag++;
  }
}

if (flag)
{
  security_report_v4(
    port       : 0,
    severity   : SECURITY_HOLE,
    extra      : deb_report_get()
  );
  exit(0);
}
else
{
  var tested = deb_pkg_tests_get();
  if (tested) audit(AUDIT_PACKAGE_NOT_AFFECTED, tested);
  else audit(AUDIT_PACKAGE_NOT_INSTALLED, 'libnginx-mod-http-auth-pam / libnginx-mod-http-cache-purge / etc');
}