AlmaLinux 9.2 [TuxCare] Security Update: openssl / openssl-devel / openssl-libs / openssl-perl Multiple Vulnerabilities (ALMALINUX9.2:CLSA-2026:1792414477)

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

include('compat.inc');

if (description)
{
  script_id(367372);
  script_version("1.1");
  script_set_attribute(attribute:"plugin_modification_date", value:"2026/10/19");

  script_cve_id("CVE-2026-54872", "CVE-2026-75805", "CVE-2026-75806");
  script_xref(name:"CLSA", value:"2026:1792414477");

  script_name(english:"AlmaLinux 9.2 [TuxCare] Security Update: openssl / openssl-devel / openssl-libs / openssl-perl Multiple Vulnerabilities (ALMALINUX9.2:CLSA-2026:1792414477)");

  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-2026:1792414477 advisory.

  - Issue summary: The generic elliptic-curve scalar multiplication used for ECDSA and SM2 signature
    operations with curves that do not have a dedicated implementation leaks information about the secret
    nonce through timing. Impact summary: An attacker able to measure signing times may learn information
    about the per-signature secret nonce, which over many signatures can, via a lattice / Hidden Number
    Problem attack, lead to recovery of the private key. CWE: CWE-208: Observable Timing Discrepancy
    Description: The generic elliptic-curve scalar multiplication used for curves that do not have a dedicated
    constant-time implementation pads the secret scalar with non-constant-time BIGNUM operations, so the time
    taken depends on the value of the secret scalar derived from the ECDSA and SM2 nonce. The leak is very
    small; observing it requires a large number of measurements. The effect is largest for curves whose group
    order lies on a machine-word boundary, such as brainpoolP384r1. Applications using ECDSA signing over the
    Brainpool and other generic prime curves, and SM2 signing on platforms that use the generic
    implementation, are vulnerable to this issue. The NIST curves P-256, P-384 and P-521 use dedicated
    constant-time implementations and are not affected. FIPS Impact: no The FIPS modules are not affected: the
    approved NIST curves used in the FIPS provider have dedicated constant-time implementations and do not use
    the affected code path. (CVE-2026-54872)

  - Issue summary: A CMP client that requests certificate revocation on the basis of a PKCS#10 CSR may
    dereference a NULL pointer and terminate abnormally when processing a crafted revocation response. Impact
    summary: The NULL pointer dereference happens on a read which leads to a crash and a Denial of Service for
    the affected client application. CWE: CWE-476: NULL-pointer dereference Description: A CMP client revoking
    a certificate has to tell the server which certificate to revoke, and may do so by supplying a PKCS#10 CSR
    instead of the certificate itself or its issuer name and serial number. This is 'openssl cmp -cmd rr -csr
    <file>' on the command line, or OSSL_CMP_exec_RR_ses() with the certificate supplied via
    OSSL_CMP_CTX_set1_p10CSR() through the API. A CSR does not contain the issuer name and serial number of
    the certificate, so the client does not send them. A server may optionally name the certificate it revoked
    in its response, and the client then compares that name against what it sent. Having sent neither an
    issuer name nor a serial number, it has nothing to compare against, and a server returning a specially
    crafted name causes the client to read from a NULL pointer and crash. The revocation response is checked
    for valid message protection before the affected code is reached, so an attacker must be a malicious or
    compromised CMP server, or a man-in-the-middle in possession of the secret used for message protection.
    Clients that identify the certificate to be revoked by a certificate or by issuer and serial number rather
    than by a PKCS#10 CSR are not affected. FIPS impact: no No FIPS modules are affected by this issue, as the
    CMP protocol implementation is outside the OpenSSL FIPS module boundary. (CVE-2026-75805)

  - Issue summary: An established DTLS 1.2 association using an AEAD cipher suite can be terminated by a
    single unauthenticated datagram whose encrypted fragment is shorter than the mandatory explicit IV and
    authentication tag overhead. Impact summary: An attacker who can send a datagram that is routed to an
    existing DTLS 1.2 association can tear that association down without knowing any key material. This is a
    Denial of Service limited to the targeted association. There is no memory safety or confidentiality
    impact. CWE: CWE-1284: Improper Validation of Specified Quantity in Input Description: In TLS 1.2 and DTLS
    1.2 every record protected by an AEAD cipher suite carries an explicit IV followed by the ciphertext and
    an authentication tag. When decrypting such a record the record layer passed the record length to the
    cipher implementation before checking that the record was long enough to contain the explicit IV and the
    tag. For a record shorter than that overhead the cipher implementation rejected the impossible length, and
    the record layer treated this as an internal failure and raised a fatal internal_error alert instead of
    treating the record as one that failed authentication. In TLS 1.2 the same record causes a fatal
    internal_error alert instead of the expected bad_record_mac alert. Since any undecryptable record already
    terminates a TLS connection, this is a protocol conformance issue rather than a security issue in TLS. The
    fix validates the record length against the explicit IV and tag length before any AEAD processing, so that
    TLS reports bad_record_mac and DTLS silently discards the record. FIPS impact: no The affected code is
    outside the FIPS module boundary. (CVE-2026-75806)

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_1792414477.json
  script_set_attribute(attribute:"see_also", value:"http://www.nessus.org/u?9badad6d");
  script_set_attribute(attribute:"see_also", value:"https://cve.tuxcare.com/els/releases/CLSA-2026:1792414477");
  script_set_attribute(attribute:"solution", value:
"Update the affected packages based on the guidance in TuxCare advisory ALMALINUX9.2:CLSA-2026:1792414477.");
  script_set_cvss_base_vector("CVSS2#AV:N/AC:H/Au:N/C:P/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:H/PR:N/UI:N/S:U/C:L/I:N/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-2026-54872");

  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:"2026/09/29");
  script_set_attribute(attribute:"patch_publication_date", value:"2026/10/19");
  script_set_attribute(attribute:"plugin_publication_date", value:"2026/10/19");

  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 ('aarch64' >!< cpu && 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.els26', 'sp':'2', 'cpu':'aarch64', 'el_string':'el9_2', 'rpm_spec_vers_cmp':TRUE, 'epoch':'1'},
      {'reference':'openssl-3.0.7-20.el9_2.tuxcare.1.els26', 'sp':'2', 'cpu':'i686', 'el_string':'el9_2', 'rpm_spec_vers_cmp':TRUE, 'epoch':'1'},
      {'reference':'openssl-3.0.7-20.el9_2.tuxcare.1.els26', '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.els26', 'sp':'2', 'cpu':'aarch64', 'el_string':'el9_2', 'rpm_spec_vers_cmp':TRUE, 'epoch':'1'},
      {'reference':'openssl-devel-3.0.7-20.el9_2.tuxcare.1.els26', '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.els26', '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.els26', 'sp':'2', 'cpu':'aarch64', 'el_string':'el9_2', 'rpm_spec_vers_cmp':TRUE, 'epoch':'1'},
      {'reference':'openssl-libs-3.0.7-20.el9_2.tuxcare.1.els26', '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.els26', '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.els26', 'sp':'2', 'cpu':'aarch64', 'el_string':'el9_2', 'rpm_spec_vers_cmp':TRUE, 'epoch':'1'},
      {'reference':'openssl-perl-3.0.7-20.el9_2.tuxcare.1.els26', 'sp':'2', 'cpu':'i686', 'el_string':'el9_2', 'rpm_spec_vers_cmp':TRUE, 'epoch':'1'},
      {'reference':'openssl-perl-3.0.7-20.el9_2.tuxcare.1.els26', '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_NOTE,
      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');
}