AlmaLinux 9.2 [TuxCare] Security Update: openssl / openssl-devel / openssl-libs / openssl-perl Multiple Vulnerabilities (ALMALINUX9.2:CLSA-2026:1782976762)

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

include('compat.inc');

if (description)
{
  script_id(362281);
  script_version("1.1");
  script_set_attribute(attribute:"plugin_modification_date", value:"2026/10/01");

  script_cve_id("CVE-2026-9076", "CVE-2026-45446");
  script_xref(name:"CLSA", value:"2026:1782976762");

  script_name(english:"AlmaLinux 9.2 [TuxCare] Security Update: openssl / openssl-devel / openssl-libs / openssl-perl Multiple Vulnerabilities (ALMALINUX9.2:CLSA-2026:1782976762)");

  script_set_attribute(attribute:"synopsis", value:
"The AlmaLinux host is missing one or more security updates.");
  script_set_attribute(attribute:"description", value:
"The AlmaLinux 9.2 host has packages installed that are affected by multiple vulnerabilities as referenced in the TuxCare
ALMALINUX9.2:CLSA-2026:1782976762 advisory.

  - Issue summary: The implementations of AES-SIV (RFC 5297) and AES-GCM-SIV (RFC 8452) mishandle the
    authentication of AAD (Additional Authenticated Data) with an empty ciphertext allowing a forgery of such
    messages. Impact summary: An attacker can forge empty messages with arbitrary AAD to the victim's
    application using these ciphers. AES-SIV (RFC 5297) and AES-GCM-SIV (RFC 8452) are nonce-misuse-resistant
    AEAD modes: they accept a key, nonce, optional AAD (bytes that are authenticated but not encrypted), and
    plaintext, and produces ciphertext plus a 16-byte tag. On decrypt, `EVP_DecryptFinal_ex()` is documented
    to return success only if the tag is verified succesfully. In OpenSSL's provider implementation of these
    ciphers, the expected tag is computed only when decryption function is invoked with non-empty data. If the
    caller supplies AAD and then calls `EVP_DecryptFinal_ex()` without invocation of the ciphertext update,
    which can happen when the received ciphertext length is zero, the tag is never recalculated and still
    holds its all-zeros value. When AES-GCM-SIV is used, an attacker who sends arbitrary AAD, empty
    ciphertext, and all-zeros tag passes authentication under any key they do not know, single-shot. When AES-
    SIV is used, for mounting the attack it's necessary for the application to reuse the decryption context
    without resetting the key. AES-SIV is implemented since OpenSSL 3.0. AES-GCM-SIV is implemented since
    OpenSSL 3.2. No protocols implemented in OpenSSL itself (TLS/CMS/PKCS7/HPKE/QUIC) support either AES-GCM-
    SIV or AES-SIV. To mount an attack, the applications must implement their own protocol and use the EVP
    interface. Also they must skip the ciphertext update when a message with an empty ciphertext arrives. The
    FIPS modules in 4.0, 3.6, 3.5, 3.4, and 3.0 are not affected by this issue, as these algorithms are not
    FIPS approved and the affected code is outside the OpenSSL FIPS module boundary. (CVE-2026-45446)

  - Issue summary: When CMS password-based decryption (RFC 3211 / PWRI key unwrap) processes attacker-supplied
    CMS data, an attacker-chosen stream-mode KEK cipher can trigger a heap out-of-bounds read in
    kek_unwrap_key(). Impact summary: A heap buffer over-read may trigger a crash which leads to Denial of
    Service for an application if the input buffer ends at a memory page boundary and the following page is
    unmapped. There is no information disclosure as the over-read bytes are not revealed to the attacker. The
    key unwrapping function performs a check-byte test as specified in the RFC that reads 7 bytes from a heap
    allocation that is based on the wrapped key length from the message. There is a minimum length check based
    on the block length of the wrapping cipher. However the cipher is selected from an OID carried in the
    attacker's PWRI keyEncryptionAlgorithm with no requirement that the cipher be a block cipher. When an
    attacker selects a stream-mode cipher the guard will be ineffective and the allocated buffer containing
    the unwrapped key can be too small to fit the check-bytes specified in the RFC and a buffer over-read can
    happen. Applications calling CMS_decrypt() or CMS_decrypt_set1_password() (equivalently openssl cms
    -decrypt -pwri_password ...) on untrusted CMS data are vulnerable to this issue. No password knowledge is
    required: the over-read happens during the unwrap attempt before any authentication succeeds. The over-
    read is limited to a few bytes and is not written to output, so there is no information disclosure.
    Triggering a crash requires the allocation to border unmapped memory, which is unlikely with the normal
    allocator. The FIPS modules are not affected by this issue. (CVE-2026-9076)

Note that Nessus has not tested for these issues but has instead relied only on the application's self-reported version
number.");
  # https://security.tuxcare.com/csaf/v2/els_os/almalinux9.2esu/advisories/2026/clsa-2026_1782976762.json
  script_set_attribute(attribute:"see_also", value:"http://www.nessus.org/u?a39a7ede");
  script_set_attribute(attribute:"see_also", value:"https://cve.tuxcare.com/els/releases/CLSA-2026:1782976762");
  script_set_attribute(attribute:"solution", value:
"Update the affected packages based on the guidance in TuxCare advisory ALMALINUX9.2:CLSA-2026:1782976762.");
  script_set_cvss_base_vector("CVSS2#AV:N/AC:L/Au:N/C:N/I:P/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:H/PR:N/UI:N/S:U/C:L/I:L/A:N");
  script_set_cvss3_temporal_vector("CVSS:3.0/E:U/RL:O/RC:C");
  script_set_attribute(attribute:"cvss_score_source", value:"CVE-2026-45446");

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

  script_set_attribute(attribute:"vuln_publication_date", value:"2026/06/09");
  script_set_attribute(attribute:"patch_publication_date", value:"2026/07/02");
  script_set_attribute(attribute:"plugin_publication_date", value:"2026/10/01");

  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:"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_info2.nasl");
  script_require_keys("Host/OS/extended-third-party", "Host/local_checks_enabled", "Host/AlmaLinux/release", "Host/AlmaLinux/rpm-list", "Host/cpu");

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

var third_party_support = get_kb_item('Host/OS/extended-third-party');
if (empty_or_null(third_party_support) || third_party_support != 'TuxCare') exit(0, 'TuxCare support not enabled.');

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:"^9.2([^0-9]|$)", string:os_version)) audit(AUDIT_OS_NOT, 'AlmaLinux 9.2', '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 (cpu !~ "^i[3-6]86$" && 'x86_64' >!< cpu) audit(AUDIT_LOCAL_CHECKS_NOT_IMPLEMENTED, 'AlmaLinux', cpu);


var constraints = [
  {
    'release': '9',
    'sp': '2',
    'pkgs': [
      {'reference':'openssl-3.0.7-20.el9_2.tuxcare.1.els20', 'sp':'2', 'cpu':'x86_64', 'el_string':'el9_2', 'rpm_spec_vers_cmp':TRUE, 'epoch':'1'},
      {'reference':'openssl-devel-3.0.7-20.el9_2.tuxcare.1.els20', 'sp':'2', 'cpu':'i686', 'el_string':'el9_2', 'rpm_spec_vers_cmp':TRUE, 'epoch':'1'},
      {'reference':'openssl-devel-3.0.7-20.el9_2.tuxcare.1.els20', 'sp':'2', 'cpu':'x86_64', 'el_string':'el9_2', 'rpm_spec_vers_cmp':TRUE, 'epoch':'1'},
      {'reference':'openssl-libs-3.0.7-20.el9_2.tuxcare.1.els20', 'sp':'2', 'cpu':'i686', 'el_string':'el9_2', 'rpm_spec_vers_cmp':TRUE, 'epoch':'1'},
      {'reference':'openssl-libs-3.0.7-20.el9_2.tuxcare.1.els20', 'sp':'2', 'cpu':'x86_64', 'el_string':'el9_2', 'rpm_spec_vers_cmp':TRUE, 'epoch':'1'},
      {'reference':'openssl-perl-3.0.7-20.el9_2.tuxcare.1.els20', 'sp':'2', 'cpu':'x86_64', 'el_string':'el9_2', 'rpm_spec_vers_cmp':TRUE, 'epoch':'1'}
    ]
  }
];

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, 'openssl / openssl-devel / openssl-libs / openssl-perl');
}