Debian DLA-3066-1 : isync - LTS security update

#
# (C) Tenable, Inc.
#
# The descriptive text and package checks in this plugin were
# extracted from Debian Security Advisory dla-3066. The text
# itself is copyright (C) Software in the Public Interest, Inc.
#

include('compat.inc');

if (description)
{
  script_id(162682);
  script_version("1.3");
  script_set_attribute(attribute:"plugin_modification_date", value:"2023/10/19");

  script_cve_id("CVE-2021-3578", "CVE-2021-3657", "CVE-2021-20247");

  script_name(english:"Debian DLA-3066-1 : isync - LTS security update");

  script_set_attribute(attribute:"synopsis", value:
"The remote Debian host is missing one or more security-related updates.");
  script_set_attribute(attribute:"description", value:
"The remote Debian 9 host has a package installed that is affected by multiple vulnerabilities as referenced in the
dla-3066 advisory.

  - A flaw was found in mbsync before v1.3.5 and v1.4.1. Validations of the mailbox names returned by IMAP
    LIST/LSUB do not occur allowing a malicious or compromised server to use specially crafted mailbox names
    containing '..' path components to access data outside the designated mailbox on the opposite end of the
    synchronization channel. The highest threat from this vulnerability is to data confidentiality and
    integrity. (CVE-2021-20247)

  - A flaw was found in mbsync before v1.3.6 and v1.4.2, where an unchecked pointer cast allows a malicious or
    compromised server to write an arbitrary integer value past the end of a heap-allocated structure by
    issuing an unexpected APPENDUID response. This could be plausibly exploited for remote code execution on
    the client. (CVE-2021-3578)

  - A flaw was found in mbsync versions prior to 1.4.4. Due to inadequate handling of extremely large (>=2GiB)
    IMAP literals, malicious or compromised IMAP servers, and hypothetically even external email senders,
    could cause several different buffer overflows, which could conceivably be exploited for remote code
    execution. (CVE-2021-3657)

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://bugs.debian.org/cgi-bin/bugreport.cgi?bug=983351");
  script_set_attribute(attribute:"see_also", value:"https://security-tracker.debian.org/tracker/source-package/isync");
  script_set_attribute(attribute:"see_also", value:"https://www.debian.org/lts/security/2022/dla-3066");
  script_set_attribute(attribute:"see_also", value:"https://security-tracker.debian.org/tracker/CVE-2021-20247");
  script_set_attribute(attribute:"see_also", value:"https://security-tracker.debian.org/tracker/CVE-2021-3578");
  script_set_attribute(attribute:"see_also", value:"https://security-tracker.debian.org/tracker/CVE-2021-3657");
  script_set_attribute(attribute:"see_also", value:"https://packages.debian.org/source/stretch/isync");
  script_set_attribute(attribute:"solution", value:
"Upgrade the isync packages.

For Debian 9 stretch, these problems have been fixed in version 1.2.1-2+deb9u1.");
  script_set_cvss_base_vector("CVSS2#AV:N/AC:L/Au:N/C:P/I:P/A:P");
  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: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-2021-3657");

  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:"2021/02/22");
  script_set_attribute(attribute:"patch_publication_date", value:"2022/07/01");
  script_set_attribute(attribute:"plugin_publication_date", value:"2022/07/01");

  script_set_attribute(attribute:"plugin_type", value:"local");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:debian:debian_linux:isync");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:debian:debian_linux:9.0");
  script_end_attributes();

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

  script_copyright(english:"This script is Copyright (C) 2022-2023 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 release = get_kb_item('Host/Debian/release');
if ( isnull(release) ) audit(AUDIT_OS_NOT, 'Debian');
var release = chomp(release);
if (! preg(pattern:"^(9)\.[0-9]+", string:release)) audit(AUDIT_OS_NOT, 'Debian 9.0', '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': '9.0', 'prefix': 'isync', 'reference': '1.2.1-2+deb9u1'}
];

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, 'isync');
}