GLSA-202210-13 : libgcrypt: Multiple Vulnerabilities

#%NASL_MIN_LEVEL 80900
#
# (C) Tenable, Inc.
#
# @NOAGENT@
#
# The descriptive text and package checks in this plugin were
# extracted from Gentoo Linux Security Advisory GLSA 202210-13.
#
# The advisory text is Copyright (C) 2001-2021 Gentoo Foundation, Inc.
# and licensed under the Creative Commons - Attribution / Share Alike
# license. See http://creativecommons.org/licenses/by-sa/3.0/
#

include('compat.inc');

if (description)
{
  script_id(166722);
  script_version("1.3");
  script_set_attribute(attribute:"plugin_modification_date", value:"2023/10/06");

  script_cve_id("CVE-2021-33560", "CVE-2021-40528");

  script_name(english:"GLSA-202210-13 : libgcrypt: Multiple Vulnerabilities");

  script_set_attribute(attribute:"synopsis", value:
"");
  script_set_attribute(attribute:"description", value:
"The remote host is affected by the vulnerability described in GLSA-202210-13 (libgcrypt: Multiple Vulnerabilities)

  - Libgcrypt before 1.8.8 and 1.9.x before 1.9.3 mishandles ElGamal encryption because it lacks exponent
    blinding to address a side-channel attack against mpi_powm, and the window size is not chosen
    appropriately. This, for example, affects use of ElGamal in OpenPGP. (CVE-2021-33560)

  - The ElGamal implementation in Libgcrypt before 1.9.4 allows plaintext recovery because, during interaction
    between two cryptographic libraries, a certain dangerous combination of the prime defined by the
    receiver's public key, the generator defined by the receiver's public key, and the sender's ephemeral
    exponents can lead to a cross-configuration attack against OpenPGP. (CVE-2021-40528)

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://security.gentoo.org/glsa/202210-13");
  script_set_attribute(attribute:"see_also", value:"https://bugs.gentoo.org/show_bug.cgi?id=766213");
  script_set_attribute(attribute:"see_also", value:"https://bugs.gentoo.org/show_bug.cgi?id=795480");
  script_set_attribute(attribute:"see_also", value:"https://bugs.gentoo.org/show_bug.cgi?id=811900");
  script_set_attribute(attribute:"solution", value:
"All libgcrypt users should upgrade to the latest version:

          # emerge --sync
          # emerge --ask --oneshot --verbose >=dev-libs/libgcrypt-1.9.4");
  script_set_cvss_base_vector("CVSS2#AV:N/AC:L/Au:N/C:P/I:N/A:N");
  script_set_cvss_temporal_vector("CVSS2#E:F/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:F/RL:O/RC:C");
  script_set_attribute(attribute:"cvss_score_source", value:"CVE-2021-33560");

  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:"2021/06/08");
  script_set_attribute(attribute:"patch_publication_date", value:"2022/10/31");
  script_set_attribute(attribute:"plugin_publication_date", value:"2022/10/31");

  script_set_attribute(attribute:"plugin_type", value:"local");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:gentoo:linux:libgcrypt");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:gentoo:linux");
  script_end_attributes();

  script_category(ACT_GATHER_INFO);
  script_family(english:"Gentoo 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/Gentoo/release", "Host/Gentoo/qpkg-list");

  exit(0);
}
include('qpkg.inc');

if (!get_kb_item('Host/local_checks_enabled')) audit(AUDIT_LOCAL_CHECKS_NOT_ENABLED);
if (!get_kb_item('Host/Gentoo/release')) audit(AUDIT_OS_NOT, 'Gentoo');
if (!get_kb_item('Host/Gentoo/qpkg-list')) audit(AUDIT_PACKAGE_LIST_MISSING);

var flag = 0;

var packages = [
  {
    'name' : 'dev-libs/libgcrypt',
    'unaffected' : make_list("ge 1.9.4", "lt 1.0.0"),
    'vulnerable' : make_list("lt 1.9.4")
  }
];

foreach package( packages ) {
  if (isnull(package['unaffected'])) package['unaffected'] = make_list();
  if (isnull(package['vulnerable'])) package['vulnerable'] = make_list();
  if (qpkg_check(package: package['name'] , unaffected: package['unaffected'], vulnerable: package['vulnerable'])) flag++;
}

# This plugin has a different number of unaffected and vulnerable versions for
# one or more packages. To ensure proper detection, a separate line should be 
# used for each fixed/vulnerable version pair.

if (flag)
{
  security_report_v4(
    port       : 0,
    severity   : SECURITY_WARNING,
    extra      : qpkg_report_get()
  );
  exit(0);
}
else
{
  qpkg_tests = list_uniq(qpkg_tests);
  var tested = qpkg_tests_get();
  if (tested) audit(AUDIT_PACKAGE_NOT_AFFECTED, tested);
  else audit(AUDIT_PACKAGE_NOT_INSTALLED, 'libgcrypt');
}