Debian DLA-3536-1 : flask - LTS 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-3536. The text
# itself is copyright (C) Software in the Public Interest, Inc.
#

include('compat.inc');

if (description)
{
  script_id(180017);
  script_version("1.1");
  script_set_attribute(attribute:"plugin_modification_date", value:"2023/10/16");

  script_cve_id("CVE-2023-30861");

  script_name(english:"Debian DLA-3536-1 : flask - LTS 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 10 host has packages installed that are affected by a vulnerability as referenced in the dla-3536
advisory.

  - Flask is a lightweight WSGI web application framework. When all of the following conditions are met, a
    response containing data intended for one client may be cached and subsequently sent by the proxy to other
    clients. If the proxy also caches `Set-Cookie` headers, it may send one client's `session` cookie to other
    clients. The severity depends on the application's use of the session and the proxy's behavior regarding
    cookies. The risk depends on all these conditions being met. 1. The application must be hosted behind a
    caching proxy that does not strip cookies or ignore responses with cookies. 2. The application sets
    `session.permanent = True` 3. The application does not access or modify the session at any point during a
    request. 4. `SESSION_REFRESH_EACH_REQUEST` enabled (the default). 5. The application does not set a
    `Cache-Control` header to indicate that a page is private or should not be cached. This happens because
    vulnerable versions of Flask only set the `Vary: Cookie` header when the session is accessed or modified,
    not when it is refreshed (re-sent to update the expiration) without being accessed or modified. This issue
    has been fixed in versions 2.3.2 and 2.2.5. (CVE-2023-30861)

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/flask");
  script_set_attribute(attribute:"see_also", value:"https://www.debian.org/lts/security/2023/dla-3536");
  script_set_attribute(attribute:"see_also", value:"https://security-tracker.debian.org/tracker/CVE-2023-30861");
  script_set_attribute(attribute:"see_also", value:"https://packages.debian.org/source/buster/flask");
  script_set_attribute(attribute:"solution", value:
"Upgrade the flask packages.

For Debian 10 buster, this problem has been fixed in version 1.0.2-3+deb10u1.");
  script_set_cvss_base_vector("CVSS2#AV:N/AC:L/Au:N/C:C/I:N/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:H/I:N/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-2023-30861");

  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:"2023/05/02");
  script_set_attribute(attribute:"patch_publication_date", value:"2023/08/20");
  script_set_attribute(attribute:"plugin_publication_date", value:"2023/08/22");

  script_set_attribute(attribute:"plugin_type", value:"local");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:debian:debian_linux:python-flask");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:debian:debian_linux:python-flask-doc");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:debian:debian_linux:python3-flask");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:debian:debian_linux:10.0");
  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) 2023 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:"^(10)\.[0-9]+", string:debian_release)) audit(AUDIT_OS_NOT, 'Debian 10.0', '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': '10.0', 'prefix': 'python-flask', 'reference': '1.0.2-3+deb10u1'},
    {'release': '10.0', 'prefix': 'python-flask-doc', 'reference': '1.0.2-3+deb10u1'},
    {'release': '10.0', 'prefix': 'python3-flask', 'reference': '1.0.2-3+deb10u1'}
];

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, 'python-flask / python-flask-doc / python3-flask');
}