Debian dsa-5728 : exim4 - security update

#%NASL_MIN_LEVEL 80900
#
# (C) Tenable, Inc.
#
# The descriptive text and package checks in this plugin were
# extracted from Debian Security Advisory dsa-5728. The text
# itself is copyright (C) Software in the Public Interest, Inc.
#

include('compat.inc');

if (description)
{
  script_id(202168);
  script_version("1.4");
  script_set_attribute(attribute:"plugin_modification_date", value:"2024/07/19");

  script_cve_id("CVE-2024-39929");
  script_xref(name:"IAVA", value:"2024-A-0416");

  script_name(english:"Debian dsa-5728 : exim4 - 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 dsa-5728
advisory.

    - -------------------------------------------------------------------------
    Debian Security Advisory DSA-5728-1                   [email protected]
    https://www.debian.org/security/                     Salvatore Bonaccorso
    July 10, 2024                         https://www.debian.org/security/faq
    - -------------------------------------------------------------------------

    Package        : exim4
    CVE ID         : CVE-2024-39929
    Debian Bug     : 1075785

    Phillip Szelat discovered that Exim, a mail transport agent, does not
    properly parse a multiline RFC 2231 header filename, allowing a remote
    attacker to bypass a $mime_filename based extension-blocking protection
    mechanism.

    For the oldstable distribution (bullseye), this problem has been fixed
    in version 4.94.2-7+deb11u3.

    For the stable distribution (bookworm), this problem has been fixed in
    version 4.96-15+deb12u5.

    We recommend that you upgrade your exim4 packages.

    For the detailed security status of exim4 please refer to its security
    tracker page at:
    https://security-tracker.debian.org/tracker/exim4

    Further information about Debian Security Advisories, how to apply
    these updates to your system and frequently asked questions can be
    found at: https://www.debian.org/security/

    Mailing list: [email protected]

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/exim4");
  script_set_attribute(attribute:"see_also", value:"https://security-tracker.debian.org/tracker/CVE-2024-39929");
  script_set_attribute(attribute:"see_also", value:"https://packages.debian.org/source/bullseye/exim4");
  script_set_attribute(attribute:"solution", value:
"Upgrade the exim4 packages.");
  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:R/S:U/C:L/I:L/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-2024-39929");

  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:"2024/07/04");
  script_set_attribute(attribute:"patch_publication_date", value:"2024/07/10");
  script_set_attribute(attribute:"plugin_publication_date", value:"2024/07/11");

  script_set_attribute(attribute:"plugin_type", value:"local");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:debian:debian_linux:exim4");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:debian:debian_linux:exim4-base");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:debian:debian_linux:exim4-config");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:debian:debian_linux:exim4-daemon-heavy");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:debian:debian_linux:exim4-daemon-light");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:debian:debian_linux:exim4-dev");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:debian:debian_linux:eximon4");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:debian:debian_linux:11.0");
  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:"Debian Local Security Checks");

  script_copyright(english:"This script is Copyright (C) 2024 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': 'exim4', 'reference': '4.94.2-7+deb11u3'},
    {'release': '11.0', 'prefix': 'exim4-base', 'reference': '4.94.2-7+deb11u3'},
    {'release': '11.0', 'prefix': 'exim4-config', 'reference': '4.94.2-7+deb11u3'},
    {'release': '11.0', 'prefix': 'exim4-daemon-heavy', 'reference': '4.94.2-7+deb11u3'},
    {'release': '11.0', 'prefix': 'exim4-daemon-light', 'reference': '4.94.2-7+deb11u3'},
    {'release': '11.0', 'prefix': 'exim4-dev', 'reference': '4.94.2-7+deb11u3'},
    {'release': '11.0', 'prefix': 'eximon4', 'reference': '4.94.2-7+deb11u3'}
];

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, 'exim4 / exim4-base / exim4-config / exim4-daemon-heavy / etc');
}