Debian dla-4541 : opam - 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-4541. The text
# itself is copyright (C) Software in the Public Interest, Inc.
#

include('compat.inc');

if (description)
{
  script_id(307900);
  script_version("1.1");
  script_set_attribute(attribute:"plugin_modification_date", value:"2026/04/21");

  script_cve_id("CVE-2026-41082");

  script_name(english:"Debian dla-4541 : opam - 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-4541
advisory.

    - -------------------------------------------------------------------------
    Debian LTS Advisory DLA-4541-1                [email protected]
    https://www.debian.org/lts/security/               Emilio Pozuelo Monfort
    April 21, 2026                                https://wiki.debian.org/LTS
    - -------------------------------------------------------------------------

    Package        : opam
    Version        : 2.0.8-1+deb11u1
    CVE ID         : CVE-2026-41082

    Andrew Nesbitt discovered that .install file directives were
    insufficiently restricted in OPAM, a package manager for OCaml. This
    could result in directory traversal out of the package area.

    For Debian 11 bullseye, this problem has been fixed in version
    2.0.8-1+deb11u1.

    We recommend that you upgrade your opam packages.

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

    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

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/opam");
  script_set_attribute(attribute:"see_also", value:"https://security-tracker.debian.org/tracker/CVE-2026-41082");
  script_set_attribute(attribute:"see_also", value:"https://packages.debian.org/source/bullseye/opam");
  script_set_attribute(attribute:"solution", value:
"Upgrade the opam packages.");
  script_set_cvss_base_vector("CVSS2#AV:L/AC:L/Au:N/C:P/I:C/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:N/UI:N/S:U/C:L/I:H/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-2026-41082");

  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:"2026/04/16");
  script_set_attribute(attribute:"patch_publication_date", value:"2026/04/21");
  script_set_attribute(attribute:"plugin_publication_date", value:"2026/04/21");

  script_set_attribute(attribute:"plugin_type", value:"local");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:debian:debian_linux:opam");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:debian:debian_linux:opam-doc");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:debian:debian_linux:opam-installer");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:debian:debian_linux:11.0");
  script_set_attribute(attribute:"generated_plugin", value:"current");
  script_end_attributes();

  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': 'opam', 'reference': '2.0.8-1+deb11u1'},
    {'release': '11.0', 'prefix': 'opam-doc', 'reference': '2.0.8-1+deb11u1'},
    {'release': '11.0', 'prefix': 'opam-installer', 'reference': '2.0.8-1+deb11u1'}
];

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_WARNING,
    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, 'opam / opam-doc / opam-installer');
}