Amazon Linux 2 : aspell (ALAS-2026-4022)

#%NASL_MIN_LEVEL 80900
##
# (C) Tenable, Inc.
#
# The descriptive text and package checks in this plugin were
# extracted from Amazon Linux 2 Security Advisory ALAS-2026-4022.
##

include('compat.inc');

if (description)
{
  script_id(371763);
  script_version("1.1");
  script_set_attribute(attribute:"plugin_modification_date", value:"2026/10/24");

  script_cve_id(
    "CVE-2026-75818",
    "CVE-2026-75819",
    "CVE-2026-75820",
    "CVE-2026-103658"
  );

  script_name(english:"Amazon Linux 2 : aspell (ALAS-2026-4022)");

  script_set_attribute(attribute:"synopsis", value:
"The remote Amazon Linux 2 host is missing a security update.");
  script_set_attribute(attribute:"description", value:
"The version of aspell installed on the remote host is prior to 0.60.6.1-22. It is, therefore, affected by multiple
vulnerabilities as referenced in the ALAS2-2026-4022 advisory.

    A flaw was found in Aspell. An attacker could achieve arbitrary code execution or cause a Denial of
    Service (DoS) by convincing a user to process a specially crafted dictionary file. This issue occurs due
    to an integer calculation error during buffer capacity checks in the read-only dictionary loader, leading
    to a heap-based buffer overflow. (CVE-2026-103658)

    GNU Aspell prezip-bin contains a heap-based buffer overflow vulnerability in the decompressor in
    prog/prezip.c. The decompressor does not properly check buffer space, so a crafted compressed file can
    cause out-of-bounds read and write operations on the heap. An attacker who convinces a user to process a
    malicious compressed file with prezip-bin can trigger memory corruption, leading to a processs crash.



    This issue was fixed in commit 15b188437f9e0192d4ac4472ad66a4e2f62a782f which will be released in version
    0.60.8.3. (CVE-2026-75818)

    GNU Aspell contains an out-of-bounds read vulnerability in ReadOnlyDict::load() in readonly_ws.cpp. When
    loading a binary .rws dictionary file, it uses offset fields from the file header as byte indices into a
    heap buffer without validating their bounds. An attacker can trigger this by convincing a user to run
    aspell with a crafted dictionary file supplied through --master, --dict-dir, or configuration options,
    leading to heap memory disclosure or a denial of service via application crash.



    This issue was fixed in commit 941953b25031bc9104e83f58e138a664b8dedc3f which will be released in version
    0.60.8.3. (CVE-2026-75819)

    GNU Aspell contains an integer truncation vulnerability in the WritableDict::add() function in
    modules/speller/default/writable.cpp. When loading a personal wordlist, the word length is stored as a
    single byte, causing truncation for words whose length is a multiple of 256. This leads to heap
    corruption. An attacker can exploit this by convincing a user to run aspell with a crafted personal
    wordlist containing such a word, resulting in denial of service.



    This issue was fixed in commit 782ce94e4dc71eaec4ee1bd945eb3b9c47c5387d which will be released in version
    0.60.8.3. (CVE-2026-75820)

Tenable has extracted the preceding description block directly from the tested product 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://alas.aws.amazon.com//AL2/ALAS2-2026-4022.html");
  script_set_attribute(attribute:"see_also", value:"https://alas.aws.amazon.com/faqs.html");
  script_set_attribute(attribute:"see_also", value:"https://explore.alas.aws.amazon.com/CVE-2026-103658.html");
  script_set_attribute(attribute:"see_also", value:"https://explore.alas.aws.amazon.com/CVE-2026-75818.html");
  script_set_attribute(attribute:"see_also", value:"https://explore.alas.aws.amazon.com/CVE-2026-75819.html");
  script_set_attribute(attribute:"see_also", value:"https://explore.alas.aws.amazon.com/CVE-2026-75820.html");
  script_set_attribute(attribute:"solution", value:
"Run 'yum update aspell' or
  or 'yum update --advisory ALAS2-2026-4022' to update your system.");
  script_set_cvss_base_vector("CVSS2#AV:L/AC:L/Au:N/C:P/I:P/A:P");
  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:N/S:U/C:L/I:L/A:L");
  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:H/AT:N/PR:N/UI:A/VC:N/VI:N/VA:L/SC:N/SI:L/SA:N");
  script_set_attribute(attribute:"cvss4_threat_vector", value:"CVSS:4.0/E:U");
  script_set_attribute(attribute:"cvss_score_source", value:"CVE-2026-103658");
  script_set_attribute(attribute:"cvss4_score_source", value:"CVE-2026-75820");

  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:"2026/10/06");
  script_set_attribute(attribute:"patch_publication_date", value:"2026/10/24");
  script_set_attribute(attribute:"plugin_publication_date", value:"2026/10/24");

  script_set_attribute(attribute:"plugin_type", value:"local");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:amazon:linux:aspell");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:amazon:linux:aspell-debuginfo");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:amazon:linux:aspell-devel");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:amazon:linux:2");
  script_set_attribute(attribute:"generated_plugin", value:"current");
  script_end_attributes();

  script_category(ACT_GATHER_INFO);
  script_family(english:"Amazon 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_info2.nasl");
  script_require_keys("Host/local_checks_enabled", "Host/AmazonLinux/release", "Host/AmazonLinux/rpm-list");

  exit(0);
}

include("rpm2.inc");

if (!get_kb_item("Host/local_checks_enabled")) audit(AUDIT_LOCAL_CHECKS_NOT_ENABLED);

var alas_release = get_kb_item("Host/AmazonLinux/release");
if (isnull(alas_release) || !strlen(alas_release)) audit(AUDIT_OS_NOT, "Amazon Linux");
var os_ver = pregmatch(pattern: "^AL(A|\d+|-\d+)", string:alas_release);
if (isnull(os_ver)) audit(AUDIT_UNKNOWN_APP_VER, "Amazon Linux");
os_ver = os_ver[1];
if (os_ver != "2")
{
  if (os_ver == 'A') os_ver = 'AMI';
  audit(AUDIT_OS_NOT, "Amazon Linux 2", "Amazon Linux " + os_ver);
}

if (!get_kb_item("Host/AmazonLinux/rpm-list")) audit(AUDIT_PACKAGE_LIST_MISSING);

var pkgs = [
    {'reference':'aspell-0.60.6.1-22.amzn2.0.1', 'cpu':'aarch64', 'release':'AL2', 'rpm_spec_vers_cmp':TRUE},
    {'reference':'aspell-0.60.6.1-22.amzn2.0.1', 'cpu':'i686', 'release':'AL2', 'rpm_spec_vers_cmp':TRUE},
    {'reference':'aspell-0.60.6.1-22.amzn2.0.1', 'cpu':'x86_64', 'release':'AL2', 'rpm_spec_vers_cmp':TRUE},
    {'reference':'aspell-debuginfo-0.60.6.1-22.amzn2.0.1', 'cpu':'aarch64', 'release':'AL2', 'rpm_spec_vers_cmp':TRUE},
    {'reference':'aspell-debuginfo-0.60.6.1-22.amzn2.0.1', 'cpu':'i686', 'release':'AL2', 'rpm_spec_vers_cmp':TRUE},
    {'reference':'aspell-debuginfo-0.60.6.1-22.amzn2.0.1', 'cpu':'x86_64', 'release':'AL2', 'rpm_spec_vers_cmp':TRUE},
    {'reference':'aspell-devel-0.60.6.1-22.amzn2.0.1', 'cpu':'aarch64', 'release':'AL2', 'rpm_spec_vers_cmp':TRUE},
    {'reference':'aspell-devel-0.60.6.1-22.amzn2.0.1', 'cpu':'i686', 'release':'AL2', 'rpm_spec_vers_cmp':TRUE},
    {'reference':'aspell-devel-0.60.6.1-22.amzn2.0.1', 'cpu':'x86_64', 'release':'AL2', 'rpm_spec_vers_cmp':TRUE}
];

var flag = 0;
foreach var package_array ( pkgs ) {
  var reference = NULL;
  var _release = NULL;
  var sp = NULL;
  var _cpu = NULL;
  var el_string = NULL;
  var rpm_spec_vers_cmp = NULL;
  var epoch = NULL;
  var allowmaj = NULL;
  var exists_check = NULL;
  var cves = NULL;
  if (!empty_or_null(package_array['reference'])) reference = package_array['reference'];
  if (!empty_or_null(package_array['release'])) _release = package_array['release'];
  if (!empty_or_null(package_array['sp'])) sp = package_array['sp'];
  if (!empty_or_null(package_array['cpu'])) _cpu = package_array['cpu'];
  if (!empty_or_null(package_array['el_string'])) el_string = package_array['el_string'];
  if (!empty_or_null(package_array['rpm_spec_vers_cmp'])) rpm_spec_vers_cmp = package_array['rpm_spec_vers_cmp'];
  if (!empty_or_null(package_array['epoch'])) epoch = package_array['epoch'];
  if (!empty_or_null(package_array['allowmaj'])) allowmaj = package_array['allowmaj'];
  if (!empty_or_null(package_array['exists_check'])) exists_check = package_array['exists_check'];
  if (!empty_or_null(package_array['cves'])) cves = package_array['cves'];
  if (reference && _release && (!exists_check || rpm_exists(release:_release, rpm:exists_check))) {
    if (rpm_check(release:_release, 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, "aspell / aspell-debuginfo / aspell-devel");
}