Ubuntu 18.04 LTS / 20.04 LTS / 22.04 LTS / 24.04 LTS / 24.10 : Fig2dev vulnerabilities (USN-7587-1)

#%NASL_MIN_LEVEL 80900
##
# (C) Tenable, Inc.
#
# The descriptive text and package checks in this plugin were
# extracted from Ubuntu Security Notice USN-7587-1. The text
# itself is copyright (C) Canonical, Inc. See
# <https://ubuntu.com/security/notices>. Ubuntu(R) is a registered
# trademark of Canonical, Inc.
##

include('compat.inc');

if (description)
{
  script_id(240492);
  script_version("1.1");
  script_set_attribute(attribute:"plugin_modification_date", value:"2025/06/25");

  script_cve_id(
    "CVE-2020-21680",
    "CVE-2020-21682",
    "CVE-2020-21683",
    "CVE-2025-31162",
    "CVE-2025-31163",
    "CVE-2025-31164"
  );
  script_xref(name:"USN", value:"7587-1");

  script_name(english:"Ubuntu 18.04 LTS / 20.04 LTS / 22.04 LTS / 24.04 LTS / 24.10 : Fig2dev vulnerabilities (USN-7587-1)");

  script_set_attribute(attribute:"synopsis", value:
"The remote Ubuntu host is missing one or more security updates.");
  script_set_attribute(attribute:"description", value:
"The remote Ubuntu 18.04 LTS / 20.04 LTS / 22.04 LTS / 24.04 LTS / 24.10 host has packages installed that are affected by
multiple vulnerabilities as referenced in the USN-7587-1 advisory.

    Suhwan Song discovered that Fig2dev did not correctly handle certain memory operations. If a user or
    automated system were tricked into opening a specially crafted file, an attacker could possibly use this
    issue to cause a denial of service. This issue only affected Ubuntu 18.04 LTS and Ubuntu 20.04 LTS.
    (CVE-2020-21680, CVE-2020-21682, CVE-2020-21683)

    It was discovered that Fig2dev did not limit the size of certain inputs. If a user or automated system
    were tricked into opening a specially crafted file, an attacker could possibly use this issue to cause a
    denial of service. (CVE-2025-31162, CVE-2025-31163)

    It was discovered that Fig2dev did not correctly handle certain inputs. If a user or automated system were
    tricked into opening a specially crafted file, an attacker could possibly use this issue to cause a denial
    of service. This issue only affected Ubuntu 24.04 LTS and Ubuntu 24.10. (CVE-2025-31164)

Tenable has extracted the preceding description block directly from the Ubuntu security advisory.

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://ubuntu.com/security/notices/USN-7587-1");
  script_set_attribute(attribute:"solution", value:
"Update the affected fig2dev and / or transfig packages.");
  script_set_cvss_base_vector("CVSS2#AV:N/AC:M/Au:N/C:N/I:N/A:P");
  script_set_cvss_temporal_vector("CVSS2#E:POC/RL:OF/RC:C");
  script_set_cvss3_base_vector("CVSS:3.0/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:N/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-2020-21683");

  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:"2021/08/10");
  script_set_attribute(attribute:"patch_publication_date", value:"2025/06/23");
  script_set_attribute(attribute:"plugin_publication_date", value:"2025/06/25");

  script_set_attribute(attribute:"plugin_type", value:"local");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:canonical:ubuntu_linux:18.04:-:lts");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:canonical:ubuntu_linux:20.04:-:lts");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:canonical:ubuntu_linux:22.04:-:lts");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:canonical:ubuntu_linux:24.04:-:lts");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:canonical:ubuntu_linux:24.10");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:canonical:ubuntu_linux:fig2dev");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:canonical:ubuntu_linux:transfig");
  script_set_attribute(attribute:"generated_plugin", value:"current");
  script_end_attributes();

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

  script_copyright(english:"Ubuntu Security Notice (C) 2025 Canonical, Inc. / NASL script (C) 2025 and is owned by Tenable, Inc. or an Affiliate thereof.");

  script_dependencies("ssh_get_info.nasl", "ubuntu_pro_sub_detect.nasl");
  script_require_keys("Host/cpu", "Host/Ubuntu", "Host/Ubuntu/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);
var os_release = get_kb_item('Host/Ubuntu/release');
if ( isnull(os_release) ) audit(AUDIT_OS_NOT, 'Ubuntu');
os_release = chomp(os_release);
if (! ('18.04' >< os_release || '20.04' >< os_release || '22.04' >< os_release || '24.04' >< os_release || '24.10' >< os_release)) audit(AUDIT_OS_NOT, 'Ubuntu 18.04 / 20.04 / 22.04 / 24.04 / 24.10', 'Ubuntu ' + os_release);
if ( ! get_kb_item('Host/Debian/dpkg-l') ) audit(AUDIT_PACKAGE_LIST_MISSING);

var cpu = get_kb_item('Host/cpu');
if (isnull(cpu)) audit(AUDIT_UNKNOWN_ARCH);
if ('x86_64' >!< cpu && cpu !~ "^i[3-6]86$" && 's390' >!< cpu && 'aarch64' >!< cpu) audit(AUDIT_LOCAL_CHECKS_NOT_IMPLEMENTED, 'Ubuntu', cpu);
var ubuntu_pro_detected = get_kb_item('Host/Ubuntu/Pro/Services/esm-apps');
ubuntu_pro_detected = !empty_or_null(ubuntu_pro_detected);

var pro_caveat_needed = FALSE;

var pkgs = [
    {'osver': '18.04', 'pkgname': 'fig2dev', 'pkgver': '1:3.2.6a-6ubuntu1.1+esm1', 'ubuntu_pro': TRUE, 'cves': ['CVE-2020-21680', 'CVE-2020-21682', 'CVE-2020-21683', 'CVE-2025-31162', 'CVE-2025-31163']},
    {'osver': '18.04', 'pkgname': 'transfig', 'pkgver': '1:3.2.6a-6ubuntu1.1+esm1', 'ubuntu_pro': TRUE, 'cves': ['CVE-2020-21680', 'CVE-2020-21682', 'CVE-2020-21683', 'CVE-2025-31162', 'CVE-2025-31163']},
    {'osver': '20.04', 'pkgname': 'fig2dev', 'pkgver': '1:3.2.7a-7ubuntu0.1+esm1', 'ubuntu_pro': TRUE, 'cves': ['CVE-2020-21680', 'CVE-2020-21682', 'CVE-2020-21683', 'CVE-2025-31162', 'CVE-2025-31163']},
    {'osver': '22.04', 'pkgname': 'fig2dev', 'pkgver': '1:3.2.8b-1ubuntu0.1~esm1', 'ubuntu_pro': TRUE, 'cves': ['CVE-2025-31162', 'CVE-2025-31163']},
    {'osver': '24.04', 'pkgname': 'fig2dev', 'pkgver': '1:3.2.9-3ubuntu0.1~esm1', 'ubuntu_pro': TRUE, 'cves': ['CVE-2025-31162', 'CVE-2025-31163', 'CVE-2025-31164']},
    {'osver': '24.10', 'pkgname': 'fig2dev', 'pkgver': '1:3.2.9-4ubuntu0.1', 'ubuntu_pro': FALSE, 'cves': ['CVE-2025-31162', 'CVE-2025-31163', 'CVE-2025-31164']}
];

var flag = 0;
foreach var package_array ( pkgs ) {
  var osver = NULL;
  var pkgname = NULL;
  var pkgver = NULL;
  if (!empty_or_null(package_array['osver'])) osver = package_array['osver'];
  if (!empty_or_null(package_array['pkgname'])) pkgname = package_array['pkgname'];
  if (!empty_or_null(package_array['pkgver'])) pkgver = package_array['pkgver'];
  if (!empty_or_null(package_array['cves'])) cves = package_array['cves'];
  var pro_required = NULL;
  if (!empty_or_null(package_array['ubuntu_pro'])) pro_required = package_array['ubuntu_pro'];
  if (osver && pkgname && pkgver) {
    if (deb_check(release:osver, prefix:pkgname, reference:pkgver, cves:cves)) {
        flag++;
        if (!ubuntu_pro_detected && !pro_caveat_needed) pro_caveat_needed = pro_required;
    }
  }
}

if (flag)
{
  var extra = '';
  if (pro_caveat_needed) {
    extra += 'NOTE: This vulnerability check contains fixes that apply to packages only \n';
    extra += 'available in Ubuntu ESM repositories. Access to these package security updates \n';
    extra += 'require an Ubuntu Pro subscription.\n\n';
  }
  extra += ubuntu_report_get();
  security_report_v4(
    port       : 0,
    severity   : SECURITY_WARNING,
    extra      : extra
  );
  exit(0);
}
else
{
  var tested = ubuntu_pkg_tests_get();
  if (tested) audit(AUDIT_PACKAGE_NOT_AFFECTED, tested);
  else audit(AUDIT_PACKAGE_NOT_INSTALLED, 'fig2dev / transfig');
}