AlmaLinux 10 : gzip (ALSA-2026:61625)

#%NASL_MIN_LEVEL 80900
##
# (C) Tenable, Inc.
#
# The package checks in this plugin were extracted from
# AlmaLinux Security Advisory ALSA-2026:61625.
##

include('compat.inc');

if (description)
{
  script_id(342160);
  script_version("1.1");
  script_set_attribute(attribute:"plugin_modification_date", value:"2026/09/01");

  script_cve_id("CVE-2026-41991", "CVE-2026-41992");
  script_xref(name:"ALSA", value:"2026:61625");
  script_xref(name:"RHSA", value:"2026:61625");

  script_name(english:"AlmaLinux 10 : gzip (ALSA-2026:61625)");

  script_set_attribute(attribute:"synopsis", value:
"The remote AlmaLinux host is missing one or more security updates.");
  script_set_attribute(attribute:"description", value:
"The remote AlmaLinux 10 host has a package installed that is affected by multiple vulnerabilities as referenced in the
ALSA-2026:61625 advisory.

    * gzip: gzip: Arbitrary file overwrite via insecure temporary file handling in gzexe utility
    (CVE-2026-41991)
      * gzip: gzip: Information disclosure via global buffer overflow in LZH decompression (CVE-2026-41992)

Tenable has extracted the preceding description block directly from the AlmaLinux 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://errata.almalinux.org/10/ALSA-2026-61625.html");
  script_set_attribute(attribute:"see_also", value:"https://access.redhat.com/errata/RHSA-2026:61625");
  script_set_attribute(attribute:"solution", value:
"Update the affected gzip package.");
  script_set_cvss_base_vector("CVSS2#AV:N/AC:L/Au:N/C:C/I:N/A:N");
  script_set_cvss_temporal_vector("CVSS2#E:U/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:U/RL:O/RC:C");
  script_set_attribute(attribute:"cvss4_vector", value:"CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N");
  script_set_attribute(attribute:"cvss4_threat_vector", value:"CVSS:4.0/E:U");
  script_set_attribute(attribute:"cvss_score_source", value:"CVE-2026-41992");

  script_set_attribute(attribute:"exploitability_ease", value:"No known exploits are available");
  script_set_attribute(attribute:"exploit_available", value:"false");
  script_cwe_id(125, 59);

  script_set_attribute(attribute:"vuln_publication_date", value:"2026/06/29");
  script_set_attribute(attribute:"patch_publication_date", value:"2026/08/31");
  script_set_attribute(attribute:"plugin_publication_date", value:"2026/09/01");

  script_set_attribute(attribute:"plugin_type", value:"local");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:alma:linux:gzip");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:alma:linux:10");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:alma:linux:10::appstream");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:alma:linux:10::baseos");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:alma:linux:10::highavailability");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:alma:linux:10::nfv");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:alma:linux:10::powertools");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:alma:linux:10::realtime");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:alma:linux:10::resilientstorage");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:alma:linux:10::sap");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:alma:linux:10::sap_hana");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:alma:linux:10::supplementary");
  script_set_attribute(attribute:"generated_plugin", value:"current");
  script_end_attributes();

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

  script_copyright(english:"This script is Copyright (C) 2026 and is owned by Tenable, Inc. or an Affiliate thereof.");

  script_dependencies("ssh_get_info.nasl");
  script_require_keys("Host/local_checks_enabled", "Host/AlmaLinux/release", "Host/AlmaLinux/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) || 'AlmaLinux' >!< os_product) audit(AUDIT_OS_NOT, 'AlmaLinux');
var os_version = get_kb_item('installed_os/local/SSH/0/version');
if (isnull(os_version)) audit(AUDIT_UNKNOWN_APP_VER, 'AlmaLinux');
if (! preg(pattern:"^10([^0-9]|$)", string:os_version)) audit(AUDIT_OS_NOT, 'AlmaLinux 10.x', 'AlmaLinux ' + os_version);

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

var cpu = get_kb_item('Host/cpu');
if (isnull(cpu)) audit(AUDIT_UNKNOWN_ARCH);
if ('aarch64' >!< cpu && 'ppc' >!< cpu && 's390' >!< cpu && 'x86_64' >!< cpu && cpu !~ "^i[3-6]86$") audit(AUDIT_LOCAL_CHECKS_NOT_IMPLEMENTED, 'AlmaLinux', cpu);

var constraints = [
  {
    'release': '10',
    'pkgs': [
      {'reference':'gzip-1.13-4.el10_2', 'cpu':'aarch64', 'el_string':'el10_2', 'rpm_spec_vers_cmp':TRUE, 'epoch':'0'},
      {'reference':'gzip-1.13-4.el10_2', 'cpu':'ppc64le', 'el_string':'el10_2', 'rpm_spec_vers_cmp':TRUE, 'epoch':'0'},
      {'reference':'gzip-1.13-4.el10_2', 'cpu':'s390x', 'el_string':'el10_2', 'rpm_spec_vers_cmp':TRUE, 'epoch':'0'},
      {'reference':'gzip-1.13-4.el10_2', 'cpu':'x86_64', 'el_string':'el10_2', 'rpm_spec_vers_cmp':TRUE, 'epoch':'0'},
      {'reference':'gzip-1.13-4.el10_2', 'cpu':'x86_64_v2', 'el_string':'el10_2', 'rpm_spec_vers_cmp':TRUE, 'epoch':'0'}
    ]
  }
];

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_HOLE,
      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, 'gzip');
}