Linux Distros Unpatched Vulnerability : CVE-2026-42393

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

include('compat.inc');

if (description)
{
  script_id(341514);
  script_version("1.1");
  script_set_attribute(attribute:"plugin_modification_date", value:"2026/08/29");

  script_cve_id("CVE-2026-42393");

  script_name(english:"Linux Distros Unpatched Vulnerability : CVE-2026-42393");

  script_set_attribute(attribute:"synopsis", value:
"The Linux/Unix host has one or more packages installed with a vulnerability that the vendor indicates will not be
patched.");
  script_set_attribute(attribute:"description", value:
"The Linux/Unix host has one or more packages installed that are impacted by a vulnerability without a vendor supplied
patch available.

  - The comparison used for the doveadm password and API key is not fully timing safe and can reveal the
    length of the configured secret. An attacker with access to the same network as the doveadm service, able
    to make repeated requests and measure response timing accurately, can learn the length of the secret,
    which reduces the effort needed to guess it. The secret value itself is not disclosed. Restrict network
    access to the doveadm service to trusted clients. Update to non-vulnerable version. No publicly available
    exploits are known. (CVE-2026-42393)

Note that Nessus relies on the presence of the package as reported by the vendor.");
  script_set_attribute(attribute:"see_also", value:"https://security-tracker.debian.org/tracker/CVE-2026-42393");
  script_set_attribute(attribute:"solution", value:
"There is no known solution at this time.");
  script_set_attribute(attribute:"agent", value:"unix");
  script_set_cvss_base_vector("CVSS2#AV:N/AC:L/Au:N/C:P/I:P/A:P");
  script_set_cvss_temporal_vector("CVSS2#E:U/RL:U/RC:C");
  script_set_cvss3_base_vector("CVSS:3.0/AV:A/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:U/RC:C");
  script_set_attribute(attribute:"cvss_score_source", value:"CVE-2026-42393");

  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_unpatched", value:"true");

  script_set_attribute(attribute:"vuln_publication_date", value:"2026/08/28");
  script_set_attribute(attribute:"plugin_publication_date", value:"2026/08/29");

  script_set_attribute(attribute:"plugin_type", value:"local");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:debian:debian_linux:11.0");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:debian:debian_linux:12.0");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:debian:debian_linux:13.0");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:debian:debian_linux:14.0");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:debian:debian_linux:dovecot");
  script_set_attribute(attribute:"generated_plugin", value:"current");
  script_end_attributes();

  script_category(ACT_GATHER_INFO);
  script_family(english:"Misc.");

  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", "set_linux_os_id.nasl");
  script_require_keys("Host/cpu", "Host/local_checks_enabled", "global_settings/vendor_unpatched", "Host/OS/identifier");
  script_require_ports("Host/OS/Debian Linux-11", "Host/OS/Debian Linux-12", "Host/OS/Debian Linux-13", "Host/OS/Debian Linux-14");

  exit(0);
}

if (!get_kb_item("global_settings/vendor_unpatched")) exit(0, "Unpatched Vulnerabilities Detection not active.");
if (!get_kb_item("Host/local_checks_enabled")) audit(AUDIT_LOCAL_CHECKS_NOT_ENABLED);
if (empty_or_null(get_one_kb_item("Host/Debian/dpkg-l"))) audit(AUDIT_PACKAGE_LIST_MISSING);

include('linux_unpatched.inc');

var distro_constraints_array = {
  "Debian Linux-11": {
    "package_manager": "dpkg-l",
    "constraints": [
      {
        "release": "11",
        "pkgs": [
          {"reference": "dovecot-auth-lua"},
          {"reference": "dovecot-core"},
          {"reference": "dovecot-dev"},
          {"reference": "dovecot-gssapi"},
          {"reference": "dovecot-imapd"},
          {"reference": "dovecot-ldap"},
          {"reference": "dovecot-lmtpd"},
          {"reference": "dovecot-lucene"},
          {"reference": "dovecot-managesieved"},
          {"reference": "dovecot-mysql"},
          {"reference": "dovecot-pgsql"},
          {"reference": "dovecot-pop3d"},
          {"reference": "dovecot-sieve"},
          {"reference": "dovecot-solr"},
          {"reference": "dovecot-sqlite"},
          {"reference": "dovecot-submissiond"}
        ]
      }
    ]
  },
  "Debian Linux-12": {
    "package_manager": "dpkg-l",
    "constraints": [
      {
        "release": "12",
        "pkgs": [
          {"reference": "dovecot-auth-lua"},
          {"reference": "dovecot-core"},
          {"reference": "dovecot-dev"},
          {"reference": "dovecot-gssapi"},
          {"reference": "dovecot-imapd"},
          {"reference": "dovecot-ldap"},
          {"reference": "dovecot-lmtpd"},
          {"reference": "dovecot-lucene"},
          {"reference": "dovecot-managesieved"},
          {"reference": "dovecot-mysql"},
          {"reference": "dovecot-pgsql"},
          {"reference": "dovecot-pop3d"},
          {"reference": "dovecot-sieve"},
          {"reference": "dovecot-solr"},
          {"reference": "dovecot-sqlite"},
          {"reference": "dovecot-submissiond"}
        ]
      }
    ]
  },
  "Debian Linux-14": {
    "package_manager": "dpkg-l",
    "constraints": [
      {
        "release": "14",
        "pkgs": [
          {"reference": "dovecot-auth-lua"},
          {"reference": "dovecot-core"},
          {"reference": "dovecot-dev"},
          {"reference": "dovecot-flatcurve"},
          {"reference": "dovecot-gssapi"},
          {"reference": "dovecot-imapd"},
          {"reference": "dovecot-ldap"},
          {"reference": "dovecot-lmtpd"},
          {"reference": "dovecot-managesieved"},
          {"reference": "dovecot-mariadb"},
          {"reference": "dovecot-mysql"},
          {"reference": "dovecot-pgsql"},
          {"reference": "dovecot-pop3d"},
          {"reference": "dovecot-sieve"},
          {"reference": "dovecot-solr"},
          {"reference": "dovecot-sqlite"},
          {"reference": "dovecot-submissiond"}
        ]
      }
    ]
  },
  "Debian Linux-13": {
    "package_manager": "dpkg-l",
    "constraints": [
      {
        "release": "13",
        "pkgs": [
          {"reference": "dovecot-auth-lua"},
          {"reference": "dovecot-core"},
          {"reference": "dovecot-dev"},
          {"reference": "dovecot-flatcurve"},
          {"reference": "dovecot-gssapi"},
          {"reference": "dovecot-imapd"},
          {"reference": "dovecot-ldap"},
          {"reference": "dovecot-lmtpd"},
          {"reference": "dovecot-managesieved"},
          {"reference": "dovecot-mysql"},
          {"reference": "dovecot-pgsql"},
          {"reference": "dovecot-pop3d"},
          {"reference": "dovecot-sieve"},
          {"reference": "dovecot-solr"},
          {"reference": "dovecot-sqlite"},
          {"reference": "dovecot-submissiond"}
        ]
      }
    ]
  }
};

var distro_constraints_values = linux_unpatched::get_distro_constraints(distro_constraints_arr:distro_constraints_array);
if (empty_or_null(distro_constraints_values)) audit(AUDIT_HOST_NOT, 'affected');

var third_party_support = get_kb_item('Host/OS/extended-third-party');
if (!empty_or_null(third_party_support)) {
    var third_party_vendors = distro_constraints_values['third_party'];
    if (!empty_or_null(third_party_vendors)) {
        var vendor;
        foreach vendor (third_party_vendors) {
            if (vendor == third_party_support) exit(0, 'A third party management patch is available for this vulnerability from ' + vendor + '.\n');
        }
    }
}

var report = linux_unpatched::check_unpatched_constraints(distro_constraints_values:distro_constraints_values);

if (!empty_or_null(report))
{
  security_report_v4(
      port       : 0,
      severity   : SECURITY_WARNING,
      extra      : report
  );
  exit(0);
}
else
{
  audit(AUDIT_HOST_NOT, 'affected');
}