Vulnerabilities > CVE-2015-6565 - Permissions, Privileges, and Access Controls vulnerability in Openbsd Openssh 6.8/6.9

#
# (C) Tenable Network Security, Inc.
#

include("compat.inc");

if (description)
{
  script_id(85382);
  script_version("1.9");
  script_cvs_date("Date: 2018/07/16 14:09:13");

  script_cve_id(
    "CVE-2015-5600",
    "CVE-2015-6563",
    "CVE-2015-6564",
    "CVE-2015-6565"
  );
  script_bugtraq_id(75990, 76317, 76497);
  script_xref(name:"EDB-ID", value:"41173");

  script_name(english:"OpenSSH < 7.0 Multiple Vulnerabilities");
  script_summary(english:"Checks the OpenSSH banner version.");

  script_set_attribute(attribute:"synopsis", value:
"The SSH server running on the remote host is affected by multiple
vulnerabilities.");
  script_set_attribute(attribute:"description", value:
"According to its banner, the version of OpenSSH running on the remote
host is prior to 7.0. It is, therefore, affected by the following
vulnerabilities :

  - A security bypass vulnerability exists in the
    kbdint_next_device() function in file auth2-chall.c that
    allows the circumvention of MaxAuthTries during
    keyboard-interactive authentication. A remote attacker
    can exploit this issue to force the same authentication
    method to be tried thousands of times in a single pass
    by using a crafted keyboard-interactive 'devices'
    string, thus allowing a brute-force attack or causing a
    denial of service. (CVE-2015-5600)

  - A security bypass vulnerability exists in sshd due to
    improper handling of username data in
    MONITOR_REQ_PAM_INIT_CTX requests. A local attacker can
    exploit this, by sending a MONITOR_REQ_PWNAM request, to
    conduct an impersonation attack. Note that this issue
    only affects Portable OpenSSH. (CVE-2015-6563)

  - A privilege escalation vulnerability exists due to a
    use-after-free error in sshd that is triggered when
    handling a MONITOR_REQ_PAM_FREE_CTX request. A local
    attacker can exploit this to gain elevated privileges.
    Note that this issue only affects Portable OpenSSH.
    (CVE-2015-6564)

  - A local command execution vulnerability exists in sshd
    due to setting insecure world-writable permissions for
    TTYs. A local attacker can exploit this, by injecting
    crafted terminal escape sequences, to execute commands
    for logged-in users. (CVE-2015-6565)");
  script_set_attribute(attribute:"see_also", value:"http://www.openssh.com/txt/release-7.0");
  script_set_attribute(attribute:"solution", value:"Upgrade to OpenSSH 7.0 or later.");
  script_set_cvss_base_vector("CVSS2#AV:N/AC:L/Au:N/C:P/I:N/A:C");
  script_set_cvss_temporal_vector("CVSS2#E:POC/RL:OF/RC:C");
  script_set_cvss3_base_vector("CVSS:3.0/AV:L/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:H");
  script_set_cvss3_temporal_vector("CVSS:3.0/E:P/RL:O/RC:C");
  script_set_attribute(attribute:"exploitability_ease", value:"Exploits are available");
  script_set_attribute(attribute:"exploit_available", value:"true");

  script_set_attribute(attribute:"vuln_publication_date", value:"2015/07/16");
  script_set_attribute(attribute:"patch_publication_date", value:"2015/08/11");
  script_set_attribute(attribute:"plugin_publication_date", value:"2015/08/13");

  script_set_attribute(attribute:"potential_vulnerability", value:"true");
  script_set_attribute(attribute:"plugin_type", value:"remote");
  script_set_attribute(attribute:"cpe", value:"cpe:/a:openbsd:openssh");
  script_end_attributes();

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

  script_copyright(english:"This script is Copyright (C) 2015-2018 Tenable Network Security, Inc.");

  script_dependencies("ssh_detect.nasl");
  script_require_keys("Settings/ParanoidReport");
  script_require_ports("Services/ssh");

  exit(0);
}

include("audit.inc");
include("backport.inc");
include("global_settings.inc");
include("misc_func.inc");

# Ensure the port is open.
port = get_service(svc:"ssh", exit_on_fail:TRUE);

# Get banner for service.
banner = get_kb_item_or_exit("SSH/banner/"+port);

bp_banner = tolower(get_backport_banner(banner:banner));
if ("openssh" >!< bp_banner) audit(AUDIT_NOT_LISTEN, "OpenSSH", port);
if (report_paranoia < 2) audit(AUDIT_PARANOID);
if (backported) audit(code:0, AUDIT_BACKPORT_SERVICE, port, "OpenSSH");

# Check the version in the backported banner.
match = eregmatch(string:bp_banner, pattern:"openssh[-_]([0-9][-._0-9a-z]+)");
if (isnull(match)) audit(AUDIT_SERVICE_VER_FAIL, "OpenSSH", port);
version = match[1];

# Affected : < 7.0
if (
  version =~ "^[0-6]\."
)
{
  if (report_verbosity > 0)
  {
    report =
      '\n  Version source    : ' + banner +
      '\n  Installed version : ' + version +
      '\n  Fixed version     : 7.0\n';
    security_hole(port:port, extra:report);
  }
  else security_hole(port);
  exit(0);
}
else audit(AUDIT_LISTEN_NOT_VULN, "OpenSSH", port, version);

#
# (C) Tenable Network Security, Inc.
#
# The descriptive text and package checks in this plugin were  
# extracted from the FreeBSD VuXML database :
#
# Copyright 2003-2018 Jacques Vidrine and contributors
#
# Redistribution and use in source (VuXML) and 'compiled' forms (SGML,
# HTML, PDF, PostScript, RTF and so forth) with or without modification,
# are permitted provided that the following conditions are met:
# 1. Redistributions of source code (VuXML) must retain the above
#    copyright notice, this list of conditions and the following
#    disclaimer as the first lines of this file unmodified.
# 2. Redistributions in compiled form (transformed to other DTDs,
#    published online in any format, converted to PDF, PostScript,
#    RTF and other formats) must reproduce the above copyright
#    notice, this list of conditions and the following disclaimer
#    in the documentation and/or other materials provided with the
#    distribution.
# 
# THIS DOCUMENTATION IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS "AS IS"
# AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
# THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
# PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS
# BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY,
# OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT
# OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR
# BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
# WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE
# OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS DOCUMENTATION,
# EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
#

include("compat.inc");

if (description)
{
  script_id(85594);
  script_version("2.5");
  script_cvs_date("Date: 2018/11/10 11:49:44");

  script_cve_id("CVE-2015-6563", "CVE-2015-6564", "CVE-2015-6565");
  script_xref(name:"FreeBSD", value:"SA-15:22.openssh");

  script_name(english:"FreeBSD : OpenSSH -- PAM vulnerabilities (2920c449-4850-11e5-825f-c80aa9043978)");
  script_summary(english:"Checks for updated package in pkg_info output");

  script_set_attribute(
    attribute:"synopsis", 
    value:"The remote FreeBSD host is missing a security-related update."
  );
  script_set_attribute(
    attribute:"description", 
    value:
"OpenSSH 6.8 and 6.9 incorrectly set TTYs to be world-writable. Local
attackers may be able to write arbitrary messages to logged-in users,
including terminal escape sequences. Reported by Nikolay Edigaryev.

Fixed a privilege separation weakness related to PAM support.
Attackers who could successfully compromise the pre-authentication
process for remote code execution and who had valid credentials on the
host could impersonate other users.

Fixed a use-after-free bug related to PAM support that was reachable
by attackers who could compromise the pre-authentication process for
remote code execution."
  );
  script_set_attribute(
    attribute:"see_also",
    value:"http://www.openssh.com/txt/release-7.0"
  );
  # https://vuxml.freebsd.org/freebsd/2920c449-4850-11e5-825f-c80aa9043978.html
  script_set_attribute(
    attribute:"see_also",
    value:"http://www.nessus.org/u?11b954c8"
  );
  script_set_attribute(attribute:"solution", value:"Update the affected package.");
  script_set_cvss_base_vector("CVSS2#AV:L/AC:L/Au:N/C:C/I:C/A:C");

  script_set_attribute(attribute:"plugin_type", value:"local");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:freebsd:freebsd:openssh-portable");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:freebsd:freebsd");

  script_set_attribute(attribute:"vuln_publication_date", value:"2015/08/11");
  script_set_attribute(attribute:"patch_publication_date", value:"2015/08/21");
  script_set_attribute(attribute:"plugin_publication_date", value:"2015/08/24");
  script_end_attributes();

  script_category(ACT_GATHER_INFO);
  script_copyright(english:"This script is Copyright (C) 2015-2018 and is owned by Tenable, Inc. or an Affiliate thereof.");
  script_family(english:"FreeBSD Local Security Checks");

  script_dependencies("ssh_get_info.nasl");
  script_require_keys("Host/local_checks_enabled", "Host/FreeBSD/release", "Host/FreeBSD/pkg_info");

  exit(0);
}


include("audit.inc");
include("freebsd_package.inc");


if (!get_kb_item("Host/local_checks_enabled")) audit(AUDIT_LOCAL_CHECKS_NOT_ENABLED);
if (!get_kb_item("Host/FreeBSD/release")) audit(AUDIT_OS_NOT, "FreeBSD");
if (!get_kb_item("Host/FreeBSD/pkg_info")) audit(AUDIT_PACKAGE_LIST_MISSING);


flag = 0;

if (pkg_test(save_report:TRUE, pkg:"openssh-portable<7.0.p1,1")) flag++;

if (flag)
{
  if (report_verbosity > 0) security_hole(port:0, extra:pkg_report_get());
  else security_hole(0);
  exit(0);
}
else audit(AUDIT_HOST_NOT, "affected");

#
# (C) Tenable Network Security, Inc.
#

include("compat.inc");

if (description)
{
  script_id(106497);
  script_version("1.6");
  script_cvs_date("Date: 2018/07/24 18:56:11");

  script_cve_id(
    "CVE-2014-2653",
    "CVE-2015-1283",
    "CVE-2015-1416",
    "CVE-2015-1418",
    "CVE-2015-5600",
    "CVE-2015-5675",
    "CVE-2015-6563",
    "CVE-2015-6564",
    "CVE-2015-6565",
    "CVE-2015-7691",
    "CVE-2015-7692",
    "CVE-2015-7701",
    "CVE-2015-7702",
    "CVE-2015-7703",
    "CVE-2015-7704",
    "CVE-2015-7705",
    "CVE-2015-7803",
    "CVE-2015-7804",
    "CVE-2015-7848",
    "CVE-2015-7849",
    "CVE-2015-7850",
    "CVE-2015-7851",
    "CVE-2015-7852",
    "CVE-2015-7853",
    "CVE-2015-7854",
    "CVE-2015-7855",
    "CVE-2015-7871"
  );
  script_bugtraq_id(
    66459,
    75990,
    76116,
    76236,
    76317,
    76485,
    76497,
    77273,
    77274,
    77275,
    77276,
    77277,
    77278,
    77279,
    77280,
    77281,
    77282,
    77283,
    77284,
    77285,
    77286,
    77287,
    77288
  );
  script_xref(name:"FreeBSD", value:"SA-15:14.bsdpatch");
  script_xref(name:"FreeBSD", value:"SA-15:16.openssh");
  script_xref(name:"FreeBSD", value:"SA-15:18.bsdpatch");
  script_xref(name:"FreeBSD", value:"SA-15:20.expat");
  script_xref(name:"FreeBSD", value:"SA-15:21.amd64");
  script_xref(name:"FreeBSD", value:"SA-15:22.openssh");
  script_xref(name:"FreeBSD", value:"SA-15:25.ntp");
  script_xref(name:"TRA", value:"TRA-2015-04");

  script_name(english:"pfSense < 2.2.5 Multiple Vulnerabilities (SA-15_08)");
  script_summary(english:"Checks the version of pfSense.");

  script_set_attribute(attribute:"synopsis", value:
"The remote firewall host is affected by multiple vulnerabilities.");
  script_set_attribute(attribute:"description", value:
"According to its self-reported version number, the remote pfSense
install is prior to 2.2.5. It is, therefore, affected by multiple
vulnerabilities as stated in the referenced vendor advisories.");
  script_set_attribute(attribute:"see_also", value:"https://doc.pfsense.org/index.php/2.2.5_New_Features_and_Changes");
  # https://www.pfsense.org/security/advisories/pfSense-SA-15_08.webgui.asc
  script_set_attribute(attribute:"see_also", value:"http://www.nessus.org/u?ec9ba339");
  script_set_attribute(attribute:"solution", value:
"Upgrade to pfSense version 2.2.5 or later.");
  script_set_cvss_base_vector("CVSS2#AV:N/AC:M/Au:N/C:C/I:C/A:C");
  script_set_cvss_temporal_vector("CVSS2#E:POC/RL:OF/RC:C");
  script_set_cvss3_base_vector("CVSS:3.0/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H");
  script_set_cvss3_temporal_vector("CVSS:3.0/E:P/RL:O/RC:C");
  script_set_attribute(attribute:"exploitability_ease", value:"Exploits are available");
  script_set_attribute(attribute:"exploit_available", value:"true");

  script_set_attribute(attribute:"vuln_publication_date", value:"2015/09/04");
  script_set_attribute(attribute:"patch_publication_date", value:"2015/09/08");
  script_set_attribute(attribute:"plugin_publication_date", value:"2018/01/31");

  script_set_attribute(attribute:"plugin_type", value:"remote");
  script_set_attribute(attribute:"cpe", value:"cpe:/a:pfsense:pfsense");
  script_set_attribute(attribute:"cpe", value:"cpe:/a:bsdperimeter:pfsense");
  script_end_attributes();

  script_category(ACT_GATHER_INFO);
  script_family(english:"Firewalls");

  script_copyright(english:"This script is Copyright (C) 2018 and is owned by Tenable, Inc. or an Affiliate thereof.");

  script_dependencies("pfsense_detect.nbin");
  script_require_keys("Host/pfSense");

  exit(0);
}

include("vcf.inc");
include("vcf_extras.inc");

if (!get_kb_item("Host/pfSense")) audit(AUDIT_HOST_NOT, "pfSense");

app_info = vcf::pfsense::get_app_info();
constraints = [
  { "fixed_version" : "2.2.5" }
];

vcf::pfsense::check_version_and_report(
  app_info:app_info,
  constraints:constraints,
  severity:SECURITY_HOLE,
  flags:{xss:TRUE}
);

#
# (C) Tenable Network Security, Inc.
#
# The descriptive text and package checks in this plugin were
# extracted from Gentoo Linux Security Advisory GLSA 201512-04.
#
# The advisory text is Copyright (C) 2001-2015 Gentoo Foundation, Inc.
# and licensed under the Creative Commons - Attribution / Share Alike 
# license. See http://creativecommons.org/licenses/by-sa/3.0/
#

include("compat.inc");

if (description)
{
  script_id(87545);
  script_version("$Revision: 2.1 $");
  script_cvs_date("$Date: 2015/12/22 15:46:34 $");

  script_cve_id("CVE-2015-5352", "CVE-2015-5600", "CVE-2015-6563", "CVE-2015-6564", "CVE-2015-6565");
  script_xref(name:"GLSA", value:"201512-04");

  script_name(english:"GLSA-201512-04 : OpenSSH: Multiple vulnerabilities");
  script_summary(english:"Checks for updated package(s) in /var/db/pkg");

  script_set_attribute(
    attribute:"synopsis", 
    value:
"The remote Gentoo host is missing one or more security-related
patches."
  );
  script_set_attribute(
    attribute:"description", 
    value:
"The remote host is affected by the vulnerability described in GLSA-201512-04
(OpenSSH: Multiple vulnerabilities)

    Multiple vulnerabilities have been discovered in OpenSSH. Please review
      the CVE identifiers referenced below for details.
  
Impact :

  
Workaround :

    There is no known workaround at this time."
  );
  script_set_attribute(
    attribute:"see_also",
    value:"https://security.gentoo.org/glsa/201512-04"
  );
  script_set_attribute(
    attribute:"solution", 
    value:
"All openssh users should upgrade to the latest version:
      # emerge --sync
      # emerge --ask --oneshot --verbose '>=net-misc/openssh-7.1_p1-r2'"
  );
  script_set_cvss_base_vector("CVSS2#AV:N/AC:L/Au:N/C:P/I:N/A:C");

  script_set_attribute(attribute:"plugin_type", value:"local");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:gentoo:linux:openssh");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:gentoo:linux");

  script_set_attribute(attribute:"patch_publication_date", value:"2015/12/20");
  script_set_attribute(attribute:"plugin_publication_date", value:"2015/12/22");
  script_end_attributes();

  script_category(ACT_GATHER_INFO);
  script_copyright(english:"This script is Copyright (C) 2015 Tenable Network Security, Inc.");
  script_family(english:"Gentoo Local Security Checks");

  script_dependencies("ssh_get_info.nasl");
  script_require_keys("Host/local_checks_enabled", "Host/Gentoo/release", "Host/Gentoo/qpkg-list");

  exit(0);
}


include("audit.inc");
include("global_settings.inc");
include("qpkg.inc");

if (!get_kb_item("Host/local_checks_enabled")) audit(AUDIT_LOCAL_CHECKS_NOT_ENABLED);
if (!get_kb_item("Host/Gentoo/release")) audit(AUDIT_OS_NOT, "Gentoo");
if (!get_kb_item("Host/Gentoo/qpkg-list")) audit(AUDIT_PACKAGE_LIST_MISSING);


flag = 0;

if (qpkg_check(package:"net-misc/openssh", unaffected:make_list("ge 7.1_p1-r2"), vulnerable:make_list("lt 7.1_p1-r2"))) flag++;

if (flag)
{
  if (report_verbosity > 0) security_hole(port:0, extra:qpkg_report_get());
  else security_hole(0);
  exit(0);
}
else
{
  tested = qpkg_tests_get();
  if (tested) audit(AUDIT_PACKAGE_NOT_AFFECTED, tested);
  else audit(AUDIT_PACKAGE_NOT_INSTALLED, "OpenSSH");
}