Vulnerabilities > CVE-2015-6389 - Improper Authentication vulnerability in Cisco Prime Collaboration Assurance 10.5.1/10.6.0

047910
CVSS 9.0 - CRITICAL
Attack vector
NETWORK
Attack complexity
LOW
Privileges required
NONE
Confidentiality impact
PARTIAL
Integrity impact
PARTIAL
Availability impact
COMPLETE
network
low complexity
cisco
CWE-287
critical
nessus

Summary

Cisco Prime Collaboration Assurance before 11.0 has a hardcoded cmuser account, which allows remote attackers to obtain access by establishing an SSH session and leveraging knowledge of this account's password, aka Bug ID CSCus62707.

Vulnerable Configurations

Part Description Count
Application
Cisco
2

Common Weakness Enumeration (CWE)

Common Attack Pattern Enumeration and Classification (CAPEC)

  • Authentication Abuse
    An attacker obtains unauthorized access to an application, service or device either through knowledge of the inherent weaknesses of an authentication mechanism, or by exploiting a flaw in the authentication scheme's implementation. In such an attack an authentication mechanism is functioning but a carefully controlled sequence of events causes the mechanism to grant access to the attacker. This attack may exploit assumptions made by the target's authentication procedures, such as assumptions regarding trust relationships or assumptions regarding the generation of secret values. This attack differs from Authentication Bypass attacks in that Authentication Abuse allows the attacker to be certified as a valid user through illegitimate means, while Authentication Bypass allows the user to access protected material without ever being certified as an authenticated user. This attack does not rely on prior sessions established by successfully authenticating users, as relied upon for the "Exploitation of Session Variables, Resource IDs and other Trusted Credentials" attack patterns.
  • Exploiting Trust in Client (aka Make the Client Invisible)
    An attack of this type exploits a programs' vulnerabilities in client/server communication channel authentication and data integrity. It leverages the implicit trust a server places in the client, or more importantly, that which the server believes is the client. An attacker executes this type of attack by placing themselves in the communication channel between client and server such that communication directly to the server is possible where the server believes it is communicating only with a valid client. There are numerous variations of this type of attack.
  • Utilizing REST's Trust in the System Resource to Register Man in the Middle
    This attack utilizes a REST(REpresentational State Transfer)-style applications' trust in the system resources and environment to place man in the middle once SSL is terminated. Rest applications premise is that they leverage existing infrastructure to deliver web services functionality. An example of this is a Rest application that uses HTTP Get methods and receives a HTTP response with an XML document. These Rest style web services are deployed on existing infrastructure such as Apache and IIS web servers with no SOAP stack required. Unfortunately from a security standpoint, there frequently is no interoperable identity security mechanism deployed, so Rest developers often fall back to SSL to deliver security. In large data centers, SSL is typically terminated at the edge of the network - at the firewall, load balancer, or router. Once the SSL is terminated the HTTP request is in the clear (unless developers have hashed or encrypted the values, but this is rare). The attacker can utilize a sniffer such as Wireshark to snapshot the credentials, such as username and password that are passed in the clear once SSL is terminated. Once the attacker gathers these credentials, they can submit requests to the web service provider just as authorized user do. There is not typically an authentication on the client side, beyond what is passed in the request itself so once this is compromised, then this is generally sufficient to compromise the service's authentication scheme.
  • Man in the Middle Attack
    This type of attack targets the communication between two components (typically client and server). The attacker places himself in the communication channel between the two components. Whenever one component attempts to communicate with the other (data flow, authentication challenges, etc.), the data first goes to the attacker, who has the opportunity to observe or alter it, and it is then passed on to the other component as if it was never intercepted. This interposition is transparent leaving the two compromised components unaware of the potential corruption or leakage of their communications. The potential for Man-in-the-Middle attacks yields an implicit lack of trust in communication or identify between two components.

Nessus

NASL familyCISCO
NASL idCISCO_PRIME_CA_CISCO-SA-20151209-PCA.NASL
descriptionThe remote Cisco Prime Collaboration Assurance device is protected by default credentials. This is due to an undocumented account that is created during installation. A remote attacker can exploit this to log in to the system shell with the default
last seen2020-06-01
modified2020-06-02
plugin id87506
published2015-12-18
reporterThis script is Copyright (C) 2015-2019 and is owned by Tenable, Inc. or an Affiliate thereof.
sourcehttps://www.tenable.com/plugins/nessus/87506
titleCisco Prime Collaboration Assurance Default 'cmuser' Credentials (cisco-sa-20151209-pca)
code
#TRUSTED 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
#
# (C) Tenable Network Security, Inc.
#

include("compat.inc");

if (description)
{
  script_id(87506);
  script_version("1.18");

  script_cve_id("CVE-2015-6389");
  script_bugtraq_id(78738);
  script_xref(name:"CISCO-BUG-ID", value:"CSCus62707");
  script_xref(name:"CISCO-SA", value:"cisco-sa-20151209-pca");

  script_name(english:"Cisco Prime Collaboration Assurance Default 'cmuser' Credentials (cisco-sa-20151209-pca)");
  script_summary(english:"Checks the Cisco Prime Collaboration Assurance version.");

  script_set_attribute(attribute:"synopsis", value:
"The remote network management device is protected by default
credentials.");
  script_set_attribute(attribute:"description", value:
"The remote Cisco Prime Collaboration Assurance device is protected by
default credentials. This is due to an undocumented account that is
created during installation. A remote attacker can exploit this to log
in to the system shell with the default 'cmuser' user account, and
access the shell with a limited set of permissions.");
  # https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20151209-pca
  script_set_attribute(attribute:"see_also", value:"http://www.nessus.org/u?28fa8c84");
  script_set_attribute(attribute:"see_also", value:"https://tools.cisco.com/bugsearch/bug/CSCus62707");
  script_set_attribute(attribute:"solution", value:
"Upgrade to Cisco Prime Collaboration Assurance version 11.0 or later.

Alternatively, a workaround is to change the default password for the
'cmuser' account.");
  script_set_cvss_base_vector("CVSS2#AV:N/AC:L/Au:N/C:P/I:P/A:C");
  script_set_cvss_temporal_vector("CVSS2#E:U/RL:OF/RC:C");
  script_set_cvss3_base_vector("CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:H");
  script_set_cvss3_temporal_vector("CVSS:3.0/E:U/RL:O/RC:C");

  script_set_attribute(attribute:"exploitability_ease", value:"No known exploits are available");

  script_set_attribute(attribute:"vuln_publication_date", value:"2015/12/09");
  script_set_attribute(attribute:"patch_publication_date", value:"2015/12/09");
  script_set_attribute(attribute:"plugin_publication_date", value:"2015/12/18");
  script_set_attribute(attribute:"plugin_modification_date", value:"2020/06/12");
  script_set_attribute(attribute:"plugin_type", value:"remote");
  script_set_attribute(attribute:"cpe", value:"cpe:/a:cisco:prime_collaboration_assurance");
  script_set_attribute(attribute:"default_account", value:"true");
  script_end_attributes();

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

  script_copyright(english:"This script is Copyright (C) 2015-2020 and is owned by Tenable, Inc. or an Affiliate thereof.");

  script_dependencies("cisco_prime_collaboration_assurance_detect.nbin");
  script_require_keys("Host/Cisco/PrimeCollaborationAssurance/version");

  exit(0);
}

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

checking_default_account_dont_report = TRUE;

if(sshlib::get_support_level() >= sshlib::SSH_LIB_SUPPORTS_COMMANDS)
  enable_ssh_wrappers();
else disable_ssh_wrappers();

appname = "Prime Collaboration Assurance";
version = get_kb_item_or_exit("Host/Cisco/PrimeCollaborationAssurance/version");

login    = "cmuser"; # default
password = "cmuser"; # default
flag  = 0;
port  = 0;
extra = '';
report_extra = '';

# Normal version check first
# Affected : < 11.0 per vendor
if (ver_compare(ver:version, fix:"11.0.0",  strict:FALSE) < 0)
  flag++;

# Check the workaround (are default creds gone?).
if (report_paranoia < 2 && flag)
{
  # Do not try this if the user has specified
  # that only user-supplied credentials are okay.
  if (supplied_logins_only)
    audit(AUDIT_SUPPLIED_LOGINS_ONLY);

  # Setup SSH bits
  port = kb_ssh_transport();
  if (!get_port_state(port))
    audit(AUDIT_PORT_CLOSED, port);

  _ssh_socket = open_sock_tcp(port);
  if (!_ssh_socket)
    audit(AUDIT_SOCK_FAIL, port);

  # Attempt the login with default credentials.
  login_result = ssh_login(login:login, password:password);

  # If login fails just keep port at '0' for
  # the version-check reporting.
  if (login_result != 0)
  {
    ssh_close_connection();
    port = 0;
    flag = 0;
  }
  # If login successful, attempt to run 'id'
  else
  {
    ssh_cmd_output = ssh_cmd(cmd:'id', nosh:TRUE, nosudo:TRUE);
    ssh_close_connection();

    if (
      ssh_cmd_output &&
      'uid' >< ssh_cmd_output
    )
    {
      # Login okay; 'id' command okay
      report_extra =
        '\n  After authenticating, Nessus executed the "id" command ' +
        '\n  which returned :' +
        '\n' +
        '\n' +
        chomp(ssh_cmd_output) +
        '\n';
    }
    else
    {
      # Login okay; BUT perhaps account is
      # administratively required to change
      # password before running commands. Or
      # any number of other mechanisms that
      # complete the login process but do not
      # allow 'id' command.
      report_extra =
      '\n  After authenticating, Nessus attempted to execute the "id" ' +
      '\n  command, but the attempt was not successful. This could ' +
      '\n  be due to the account being administratively required to ' +
      '\n  change password at login; however, the account is indeed enabled ' +
      '\n  and accessible with the default password.';
    }
  }
}

if (port || flag)
{
  if (report_verbosity > 0)
  {
    report +=
      '\n  Installed version : ' + version +
      '\n  Fixed version     : 11.0' +
      '\n';
    if (report_paranoia == 2)
      report_extra +=
        '\n  Note that Nessus has not attempted to login as the "cmuser" due' +
        '\n  this scan being configured as Paranoid.' +
        '\n';
    security_hole(port:port, extra:report + report_extra);
  }
  else security_hole(port);
  exit(0);
}
else audit(AUDIT_INST_VER_NOT_VULN, appname, version);