Alibaba Cloud Linux 3 : 0243: vim (ALINUX3-SA-2026:0243)

#%NASL_MIN_LEVEL 80900
##
# (C) Tenable, Inc.
#
# The package checks in this plugin were extracted from
# Alibaba Cloud Linux Security Advisory ALINUX3-SA-2026:0243.
##

include('compat.inc');

if (description)
{
  script_id(333572);
  script_version("1.1");
  script_set_attribute(attribute:"plugin_modification_date", value:"2026/08/10");

  script_cve_id(
    "CVE-2026-55693",
    "CVE-2026-57455",
    "CVE-2026-57456",
    "CVE-2026-59858"
  );

  script_name(english:"Alibaba Cloud Linux 3 : 0243: vim (ALINUX3-SA-2026:0243)");

  script_set_attribute(attribute:"synopsis", value:
"The remote Alibaba Cloud Linux host is missing one or more security updates.");
  script_set_attribute(attribute:"description", value:
"The remote Alibaba Cloud Linux 3 host has packages installed that are affected by multiple vulnerabilities as referenced
in the ALINUX3-SA-2026:0243 advisory.

    Package updates are available for Alibaba Cloud Linux 3 that fix the following vulnerabilities:

    CVE-2026-55693:
    Vim is an open source, command line text editor. Prior to 9.2.0653, the tree_count_words() function in
    src/spellfile.c fills in the word-count fields of a spell-file word trie by walking it iteratively with a
    depth counter. The counter is bounded only by the trie structure itself; it is never checked against the
    size of the fixed MAXWLEN-element stack arrays it indexes (arridx[], curi[], wordcount[]). A crafted
    .spl/.sug file pair, loaded when the user invokes spell suggestion, can drive the descent arbitrarily
    deep, so the function writes past the end of those arrays. This is a stack out-of-bounds write that
    corrupts the call frame and crashes the editor. This vulnerability is fixed in 9.2.0653.

    CVE-2026-57455:
    Vim is an open source, command line text editor. Prior to 9.2.0698, the single-byte branch of
    spell_soundfold_sofo() in src/spell.c translates a word through a spell file's SOFO (sound-folding) byte
    map into a caller-owned result buffer. Its copy loop advances the output index ri with no upper bound and
    terminates only on the input NUL, writing one byte per input byte into the MAXWLEN-element stack buffer
    the caller provides. A word longer than MAXWLEN, passed to soundfold() (or reached via sound-based spell
    suggestion) while a SOFO-based spell language is active, therefore writes past the end of that buffer.
    This is a stack out-of-bounds write that corrupts the call frame and crashes the editor. This
    vulnerability is fixed in 9.2.0698.

    CVE-2026-57456:
    Vim is an open source, command line text editor. Prior to 9.2.0699, Vim's Python omni-completion
    (runtime/autoload/python3complete.vim and the legacy pythoncomplete.vim) executes reconstructed function
    and class definitions from the current buffer with exec() as part of populating the completion dictionary.
    When reconstructing that source, each scope's docstring is inserted verbatim between triple quotes with no
    escaping, so a hostile buffer can break out of the triple-quoted literal and execute attacker-controlled
    Python during omni-completion. This vulnerability is fixed in 9.2.0699.

    CVE-2026-59858:
    Vim is an open source, command line text editor. Prior to 9.2.0735, the C omni-completion script in
    runtime/autoload/ccomplete.vim interpolates the typeref: or typename: extension field of a tags entry,
    without escaping, into a :vimgrep pattern that is run through :execute. Because :vimgrep honors the bar as
    a command separator, a crafted tag field can close the search pattern and append an arbitrary Ex command;
    opening a hostile .c file whose project tags file contains such an entry and invoking C omni-completion
    runs that command as the editing user. This issue is fixed in version 9.2.0735.

Tenable has extracted the preceding description block directly from the Alibaba Cloud Linux 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:"http://mirrors.aliyun.com/alinux/3/cve/alinux3-sa-20260243.xml");
  script_set_attribute(attribute:"solution", value:
"Update the affected packages.");
  script_set_cvss_base_vector("CVSS2#AV:L/AC:L/Au:N/C:C/I:C/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:H/I:H/A:H");
  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:A/VC:H/VI:H/VA:H/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-2026-59858");

  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:"2026/06/25");
  script_set_attribute(attribute:"patch_publication_date", value:"2026/08/05");
  script_set_attribute(attribute:"plugin_publication_date", value:"2026/08/10");

  script_set_attribute(attribute:"plugin_type", value:"local");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:alibabacloud:alibaba_cloud_linux_3:vim-X11");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:alibabacloud:alibaba_cloud_linux_3:vim-common");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:alibabacloud:alibaba_cloud_linux_3:vim-enhanced");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:alibabacloud:alibaba_cloud_linux_3:vim-filesystem");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:alibabacloud:alibaba_cloud_linux_3:vim-minimal");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:alibabacloud:alibaba_cloud_linux_3");
  script_set_attribute(attribute:"generated_plugin", value:"current");
  script_end_attributes();

  script_category(ACT_GATHER_INFO);
  script_family(english:"Alibaba Cloud 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/Alibaba/release", "Host/Alibaba/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) || 'Alibaba Cloud Linux' >!< os_product) audit(AUDIT_OS_NOT, 'Alibaba Cloud Linux');
var os_version = get_kb_item('installed_os/local/SSH/0/version');
if (isnull(os_version)) audit(AUDIT_UNKNOWN_APP_VER, 'Alibaba Cloud Linux');
if (! preg(pattern:"^3([^0-9]|$)", string:os_version)) audit(AUDIT_OS_NOT, 'Alibaba Cloud Linux 3.x', 'Alibaba Cloud Linux ' + os_version);

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

var cpu = get_kb_item('Host/cpu');
if (isnull(cpu)) audit(AUDIT_UNKNOWN_ARCH);
if ('aarch64' >!< cpu && 'x86_64' >!< cpu) audit(AUDIT_LOCAL_CHECKS_NOT_IMPLEMENTED, 'Alibaba Cloud Linux', cpu);

var constraints = [
  {
    'release': '3',
    'pkgs': [
      {'reference':'vim-common-8.0.1763-31.0.1.al8', 'cpu':'aarch64', 'rpm_spec_vers_cmp':TRUE, 'epoch':'0'},
      {'reference':'vim-common-8.0.1763-31.0.1.al8', 'cpu':'x86_64', 'rpm_spec_vers_cmp':TRUE, 'epoch':'0'},
      {'reference':'vim-enhanced-8.0.1763-31.0.1.al8', 'cpu':'aarch64', 'rpm_spec_vers_cmp':TRUE, 'epoch':'0'},
      {'reference':'vim-enhanced-8.0.1763-31.0.1.al8', 'cpu':'x86_64', 'rpm_spec_vers_cmp':TRUE, 'epoch':'0'},
      {'reference':'vim-filesystem-8.0.1763-31.0.1.al8', 'rpm_spec_vers_cmp':TRUE, 'epoch':'0'},
      {'reference':'vim-minimal-8.0.1763-31.0.1.al8', 'cpu':'aarch64', 'rpm_spec_vers_cmp':TRUE, 'epoch':'0'},
      {'reference':'vim-minimal-8.0.1763-31.0.1.al8', 'cpu':'x86_64', 'rpm_spec_vers_cmp':TRUE, 'epoch':'0'},
      {'reference':'vim-X11-8.0.1763-31.0.1.al8', 'cpu':'aarch64', 'rpm_spec_vers_cmp':TRUE, 'epoch':'0'},
      {'reference':'vim-X11-8.0.1763-31.0.1.al8', 'cpu':'x86_64', '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, 'vim-X11 / vim-common / vim-enhanced / vim-filesystem / vim-minimal');
}