Linux Distros Unpatched Vulnerability : CVE-2026-0394

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

include('compat.inc');

if (description)
{
  script_id(304062);
  script_version("1.6");
  script_set_attribute(attribute:"plugin_modification_date", value:"2026/05/02");

  script_cve_id("CVE-2026-0394");

  script_name(english:"Linux Distros Unpatched Vulnerability : CVE-2026-0394");

  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.

  - When dovecot has been configured to use per-domain passwd files, and they are placed one path component
    above /etc, or slash has been added to allowed characters, path traversal can happen if the domain
    component is directory partial. This allows inadvertently reading /etc/passwd (or some other path which
    ends with passwd). If this file contains passwords, it can be used to authenticate wrongly, or if this is
    userdb, it can unexpectly make system users appear valid users. Upgrade to fixed version, or use different
    authentication scheme that does not rely on paths. Alternatively you can also ensure that the per-domain
    passwd files are in some other location, such as /etc/dovecot/auth/%d. No publicly available exploits are
    known. (CVE-2026-0394)

Note that Nessus relies on the presence of the package as reported by the vendor.");
  script_set_attribute(attribute:"see_also", value:"https://access.redhat.com/security/cve/cve-2026-0394");
  script_set_attribute(attribute:"see_also", value:"https://ubuntu.com/security/CVE-2026-0394");
  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:N/A:N");
  script_set_cvss_temporal_vector("CVSS2#E:U/RL:U/RC:C");
  script_set_cvss3_base_vector("CVSS:3.0/AV:N/AC:L/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-2026-0394");

  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:"2026/03/27");
  script_set_attribute(attribute:"plugin_publication_date", value:"2026/03/28");

  script_set_attribute(attribute:"plugin_type", value:"local");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:canonical:ubuntu_linux:14.04:-:lts");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:canonical:ubuntu_linux:16.04:-:lts");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:canonical:ubuntu_linux:18.04:-:lts");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:canonical:ubuntu_linux:20.04:-:lts");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:centos:centos:7");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:redhat:enterprise_linux:7");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:canonical:ubuntu_linux:dovecot");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:centos:centos:dovecot");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:centos:centos:dovecot-devel");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:centos:centos:dovecot-mysql");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:centos:centos:dovecot-pgsql");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:centos:centos:dovecot-pigeonhole");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:redhat:enterprise_linux:dovecot");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:redhat:enterprise_linux:dovecot-devel");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:redhat:enterprise_linux:dovecot-mysql");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:redhat:enterprise_linux:dovecot-pgsql");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:redhat:enterprise_linux:dovecot-pigeonhole");
  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/CentOS Linux-7", "Host/OS/Red Hat Enterprise Linux-7", "Host/OS/Ubuntu Linux-14.04", "Host/OS/Ubuntu Linux-16.04", "Host/OS/Ubuntu Linux-18.04", "Host/OS/Ubuntu Linux-20.04");

  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/CentOS/rpm-list")) && empty_or_null(get_one_kb_item("Host/Debian/dpkg-l")) && empty_or_null(get_one_kb_item("Host/RedHat/rpm-list"))) audit(AUDIT_PACKAGE_LIST_MISSING);

include('linux_unpatched.inc');

var distro_constraints_array = {
  "Ubuntu Linux-14.04": {
    "package_manager": "dpkg-l",
    "constraints": [
      {
        "release": "14.04",
        "pkgs": [
          {"reference": "dovecot-core"},
          {"reference": "dovecot-dbg"},
          {"reference": "dovecot-dev"},
          {"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": "mail-stack-delivery"}
        ]
      }
    ]
  },
  "Ubuntu Linux-16.04": {
    "package_manager": "dpkg-l",
    "constraints": [
      {
        "release": "16.04",
        "pkgs": [
          {"reference": "dovecot-core"},
          {"reference": "dovecot-dbg"},
          {"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": "mail-stack-delivery"}
        ]
      }
    ]
  },
  "Ubuntu Linux-18.04": {
    "package_manager": "dpkg-l",
    "constraints": [
      {
        "release": "18.04",
        "pkgs": [
          {"reference": "dovecot-core"},
          {"reference": "dovecot-dev"},
          {"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": "mail-stack-delivery"}
        ]
      }
    ]
  },
  "Ubuntu Linux-20.04": {
    "package_manager": "dpkg-l",
    "constraints": [
      {
        "release": "20.04",
        "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"},
          {"reference": "mail-stack-delivery"}
        ]
      }
    ]
  },
  "CentOS Linux-7": {
    "package_manager": "rpm-list",
    "constraints": [
      {
        "release": "7",
        "pkgs": [
          {"reference": "dovecot"},
          {"reference": "dovecot-devel"},
          {"reference": "dovecot-mysql"},
          {"reference": "dovecot-pgsql"},
          {"reference": "dovecot-pigeonhole"}
        ]
      }
    ]
  },
  "Red Hat Enterprise Linux-7": {
    "package_manager": "rpm-list",
    "constraints": [
      {
        "release": "7",
        "pkgs": [
          {"reference": "dovecot"},
          {"reference": "dovecot-devel"},
          {"reference": "dovecot-mysql"},
          {"reference": "dovecot-pgsql"},
          {"reference": "dovecot-pigeonhole"}
        ]
      }
    ]
  }
};

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 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');
}