Unity Linux 20.1050a / 20.1060a / 20.1070a Security Update: libpng (UTSA-2025-991297)

#%NASL_MIN_LEVEL 80900
##
# (C) Tenable, Inc.
##

include('compat.inc');

if (description)
{
  script_id(279463);
  script_version("1.1");
  script_set_attribute(attribute:"plugin_modification_date", value:"2025/12/20");

  script_cve_id("CVE-2025-64506");

  script_name(english:"Unity Linux 20.1050a / 20.1060a / 20.1070a Security Update: libpng (UTSA-2025-991297)");

  script_set_attribute(attribute:"synopsis", value:
"The Unity Linux host is missing one or more security updates.");
  script_set_attribute(attribute:"description", value:
"The Unity Linux 20 host has a package installed that is affected by a vulnerability as referenced in the
UTSA-2025-991297 advisory.

    LIBPNG is a reference library for use in applications that read, create, and manipulate PNG (Portable
    Network Graphics) raster image files. From version 1.6.0 to before 1.6.51, a heap buffer over-read
    vulnerability exists in libpng's png_write_image_8bit function when processing 8-bit images through the
    simplified write API with convert_to_8bit enabled. The vulnerability affects 8-bit grayscale+alpha,
    RGB/RGBA, and images with incomplete row data. A conditional guard incorrectly allows 8-bit input to enter
    code expecting 16-bit input, causing reads up to 2 bytes beyond allocated buffer boundaries. This issue
    has been patched in version 1.6.51.

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

Note that Nessus has not tested for this issue but has instead relied only on the application's self-reported version
number.");
  # https://src.uniontech.com/#/security_advisory_detail?utsa_id=UTSA-2025-991297
  script_set_attribute(attribute:"see_also", value:"http://www.nessus.org/u?770adf1a");
  script_set_attribute(attribute:"see_also", value:"https://access.redhat.com/security/cve/CVE-2025-64506");
  script_set_attribute(attribute:"see_also", value:"https://nvd.nist.gov/vuln/detail/CVE-2025-64506");
  script_set_attribute(attribute:"solution", value:
"Update the affected libpng package.");
  script_set_cvss_base_vector("CVSS2#AV:L/AC:L/Au:N/C:P/I:N/A:C");
  script_set_cvss_temporal_vector("CVSS2#E:U/RL:OF/RC:C");
  script_set_cvss3_base_vector("CVSS:3.0/AV:L/AC:L/PR:N/UI:R/S:U/C:L/I:N/A:H");
  script_set_cvss3_temporal_vector("CVSS:3.0/E:U/RL:O/RC:C");
  script_set_attribute(attribute:"cvss_score_source", value:"CVE-2025-64506");

  script_set_attribute(attribute:"exploitability_ease", value:"No known exploits are available");
  script_set_attribute(attribute:"exploit_available", value:"false");

  script_set_attribute(attribute:"vuln_publication_date", value:"2025/11/24");
  script_set_attribute(attribute:"patch_publication_date", value:"2025/12/20");
  script_set_attribute(attribute:"plugin_publication_date", value:"2025/12/20");

  script_set_attribute(attribute:"plugin_type", value:"local");
  script_set_attribute(attribute:"generated_plugin", value:"current");
  script_end_attributes();

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

  script_copyright(english:"This script is Copyright (C) 2025 and is owned by Tenable, Inc. or an Affiliate thereof.");

  script_dependencies("ssh_get_info2.nasl");
  script_require_keys("Host/local_checks_enabled", "Host/UOS-Server/release", "Host/UOS-Server/rpm-list", "Host/cpu");

  exit(0);
}
include('rpm2.inc');

if (!get_kb_item('Host/local_checks_enabled')) audit(AUDIT_LOCAL_CHECKS_NOT_ENABLED);
var os_product = get_kb_item('installed_os/local/SSH/0/product');
if (isnull(os_product) || 'UOS Server' >!< os_product) audit(AUDIT_OS_NOT, 'UOS Server');
var os_version = get_kb_item('installed_os/local/SSH/0/version');
if (isnull(os_version)) audit(AUDIT_UNKNOWN_APP_VER, 'UOS Server');
if (! preg(pattern:"^20.1050a|20.1060a|20.1070a([^0-9]|$)", string:os_version)) audit(AUDIT_OS_NOT, 'UOS Server 20.1050a / 20.1060a / 20.1070a', 'UOS Server ' + os_version);

if (!get_kb_item('Host/UOS-Server/rpm-list')) audit(AUDIT_PACKAGE_LIST_MISSING);

var cpu = get_kb_item('Host/cpu');
if (isnull(cpu)) audit(AUDIT_UNKNOWN_ARCH);
if ('aarch64' >!< cpu && 'amd64' >!< cpu && 'loongarch64' >!< cpu && 'x86_64' >!< cpu) audit(AUDIT_LOCAL_CHECKS_NOT_IMPLEMENTED, 'UOS Server', cpu);


var constraints = [
  {
    'release': '20',
    'sp': '1050a',
    'pkgs': [
      {'reference':'libpng-1.6.37-3.uelc20.01', 'sp':'1050a', 'cpu':'aarch64', 'rpm_spec_vers_cmp':TRUE},
      {'reference':'libpng-1.6.37-3.uelc20.01', 'sp':'1050a', 'cpu':'amd64', 'rpm_spec_vers_cmp':TRUE},
      {'reference':'libpng-1.6.37-3.uelc20.01', 'sp':'1050a', 'cpu':'loongarch64', 'rpm_spec_vers_cmp':TRUE},
      {'reference':'libpng-1.6.37-3.uelc20.01', 'sp':'1050a', 'cpu':'x86_64', 'rpm_spec_vers_cmp':TRUE}
    ]
  },
  {
    'release': '20',
    'sp': '1060a',
    'pkgs': [
      {'reference':'libpng-1.6.37-3.uelc20.01', 'sp':'1060a', 'cpu':'aarch64', 'rpm_spec_vers_cmp':TRUE},
      {'reference':'libpng-1.6.37-3.uelc20.01', 'sp':'1060a', 'cpu':'amd64', 'rpm_spec_vers_cmp':TRUE},
      {'reference':'libpng-1.6.37-3.uelc20.01', 'sp':'1060a', 'cpu':'loongarch64', 'rpm_spec_vers_cmp':TRUE},
      {'reference':'libpng-1.6.37-3.uelc20.01', 'sp':'1060a', 'cpu':'x86_64', 'rpm_spec_vers_cmp':TRUE}
    ]
  },
  {
    'release': '20',
    'sp': '1070a',
    'pkgs': [
      {'reference':'libpng-1.6.37-3.uelc20.01', 'sp':'1070a', 'cpu':'aarch64', 'rpm_spec_vers_cmp':TRUE},
      {'reference':'libpng-1.6.37-3.uelc20.01', 'sp':'1070a', 'cpu':'amd64', 'rpm_spec_vers_cmp':TRUE},
      {'reference':'libpng-1.6.37-3.uelc20.01', 'sp':'1070a', 'cpu':'loongarch64', 'rpm_spec_vers_cmp':TRUE},
      {'reference':'libpng-1.6.37-3.uelc20.01', 'sp':'1070a', 'cpu':'x86_64', 'rpm_spec_vers_cmp':TRUE}
    ]
  }
];

var os_release = get_one_kb_item('installed_os/local/SSH/0/release');
var os_sp = get_one_kb_item('Host/*/minor_release');

var flag = 0;
var reference;
var sp;
var _cpu;
var el_string;
var rpm_spec_vers_cmp;
var epoch;
var allowmaj;
var exists_check;
var cves;
foreach var constraint ( constraints ) {
  # Check that the target release is equal to the affected release
  if (!empty_or_null(constraint['release'])){
    if (constraint['release'] != os_release) continue;
  }
  if (!empty_or_null(constraint['sp'])){
    if (constraint['sp'] != os_sp) continue;
  }
  foreach var pkg ( constraint['pkgs'] ) {
    reference = NULL;
    sp = NULL;
    _cpu = NULL;
    el_string = NULL;
    rpm_spec_vers_cmp = NULL;
    epoch = NULL;
    allowmaj = NULL;
    exists_check = NULL;
    cves = NULL;
    if (!empty_or_null(pkg['reference'])) reference = pkg['reference'];
    if (!empty_or_null(pkg['sp'])) sp = pkg['sp'];
    if (!empty_or_null(pkg['cpu'])) _cpu = pkg['cpu'];
    if (!empty_or_null(pkg['el_string'])) el_string = pkg['el_string'];
    if (!empty_or_null(pkg['rpm_spec_vers_cmp'])) rpm_spec_vers_cmp = pkg['rpm_spec_vers_cmp'];
    if (!empty_or_null(pkg['epoch'])) epoch = pkg['epoch'];
    if (!empty_or_null(pkg['allowmaj'])) allowmaj = pkg['allowmaj'];
    if (!empty_or_null(pkg['exists_check'])) exists_check = pkg['exists_check'];
    if (!empty_or_null(pkg['cves'])) cves = pkg['cves'];
    if (reference &&
        ## (no known rpm to check OR known rpm_exists)
        (!exists_check || rpm_exists(rpm:exists_check)) &&
        rpm_check(sp:sp, cpu:_cpu, reference:reference, epoch:epoch, el_string:el_string, rpm_spec_vers_cmp:rpm_spec_vers_cmp, allowmaj:allowmaj, cves:cves)) flag++;
  }
}


if (flag)
{
  security_report_v4(
      port       : 0,
      severity   : SECURITY_WARNING,
      extra      : rpm_report_get()
  );
  exit(0);
}
else
{
  var tested = pkg_tests_get();
  if (tested) audit(AUDIT_PACKAGE_NOT_AFFECTED, tested);
  else audit(AUDIT_PACKAGE_NOT_INSTALLED, 'libpng');
}