Vulnerabilities > CVE-2017-14117 - Improper Authentication vulnerability in ATT U-Verse Firmware 9.2.2H0D83

047910
CVSS 4.3 - MEDIUM
Attack vector
NETWORK
Attack complexity
MEDIUM
Privileges required
NONE
Confidentiality impact
NONE
Integrity impact
PARTIAL
Availability impact
NONE
network
att
arris
CWE-287
nessus
metasploit

Summary

The AT&T U-verse 9.2.2h0d83 firmware for the Arris NVG589 and NVG599 devices, when IP Passthrough mode is not used, configures an unauthenticated proxy service on WAN TCP port 49152, which allows remote attackers to establish arbitrary TCP connections to intranet hosts by sending \x2a\xce\x01 followed by other predictable values.

Vulnerable Configurations

Part Description Count
OS
Att
1
Hardware
Arris
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.

Metasploit

descriptionThe Arris NVG589 and NVG599 routers configured with AT&T; U-verse firmware 9.2.2h0d83 expose an un-authenticated proxy that allows connecting from WAN to LAN by MAC address.
idMSF:AUXILIARY/SCANNER/WPROXY/ATT_OPEN_PROXY
last seen2020-06-02
modified2018-08-27
published2018-01-17
references
reporterRapid7
sourcehttps://github.com/rapid7/metasploit-framework/blob/master//modules/auxiliary/scanner/wproxy/att_open_proxy.py
titleOpen WAN-to-LAN proxy on AT&T routers

Nessus

NASL familyCGI abuses
NASL idARRIS_MODEM_SHARKNATTO.NASL
descriptionThe remote Arris device
last seen2020-06-01
modified2020-06-02
plugin id102916
published2017-09-01
reporterThis script is Copyright (C) 2017-2019 and is owned by Tenable, Inc. or an Affiliate thereof.
sourcehttps://www.tenable.com/plugins/nessus/102916
titleAT&T U-verse Arris Modems NVG589 / NVG599 / 5268AC Multiple Vulnerabilities (SharknATTo)
code
#
# (C) Tenable Network Security, Inc.
#

include("compat.inc");

if (description)
{
  script_id(102916);
  script_version("1.7");
  script_cvs_date("Date: 2019/11/12");

  script_cve_id(
    "CVE-2017-10793",
    "CVE-2017-14115",
    "CVE-2017-14116",
    "CVE-2017-14117"
  );
  script_bugtraq_id(100585);

  script_name(english:"AT&T U-verse Arris Modems NVG589 / NVG599 / 5268AC Multiple Vulnerabilities (SharknATTo)");
  script_summary(english:"Looks for the product and version in the about page.");

  script_set_attribute(attribute:"synopsis", value:
"The remote device is affected by multiple vulnerabilities, including multiple
remote code execution vulnerabilities.");
  script_set_attribute(attribute:"description", value:
"The remote Arris device's self report model is NVG589, NVG599 or 5268AC.
It is, therefor, affected by multiple vulnerabilities, including a firewall
bypass, multiple instances of hardcoded credentials, privilege escalation, and
remote code execution.

Note: Nessus has not checked the firmware version and is detecting this vulnerability
based on the device's self reported model number.");
  script_set_attribute(attribute:"see_also", value:"https://www.nomotion.net/blog/sharknatto/");
  script_set_attribute(attribute:"solution", value:
"No vendor-supplied fix is currently available. Contact vendor for further details.");
  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:F/RL:U/RC:ND");
  script_set_cvss3_base_vector("CVSS:3.0/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H");
  script_set_cvss3_temporal_vector("CVSS:3.0/E:F/RL:U/RC:X");
  script_set_attribute(attribute:"cvss_score_source", value:"CVE-2017-14116");

  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:"2017/08/31");
  script_set_attribute(attribute:"plugin_publication_date", value:"2017/09/01");

  script_set_attribute(attribute:"potential_vulnerability", value:"true");
  script_set_attribute(attribute:"plugin_type", value:"remote");
  script_end_attributes();

  script_category(ACT_GATHER_INFO);
  script_family(english:"CGI abuses");

  script_copyright(english:"This script is Copyright (C) 2017-2019 and is owned by Tenable, Inc. or an Affiliate thereof.");

  script_dependencies("http_version.nasl");
  script_require_keys("Settings/ParanoidReport");
  script_require_ports("Services/www", 80, 443);

  exit(0);
}

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

if (report_paranoia < 2) audit(AUDIT_PARANOID);

port     = get_http_port(default:80);
item = "/xslt?PAGE=C_0_0";
vuln = FALSE;

res = http_send_recv3(method:"GET", item:item, port:port);
if (!isnull(res[2])  && '<a href="/xslt?PAGE=C_2_0">LAN</a>' >< res[2] && '<a href="/xslt?PAGE=C_3_0">Firewall</a>' >< res[2])
{
  pat = "<td>(NVG59[89]|5268AC)</td>";
  match = pregmatch(string:res[2], pattern:pat);
  if (!isnull(match))
  {
    model  = match[1];
    vuln = TRUE;
  }
}

if(vuln)
{
  report = '\nBased on its self-reported model number the remote device is vulnerable.\n';
  report += '\n    Model : ' + model;
  report += '\n    Fix   : Contact vendor for further details.\n';
  security_report_v4(severity:SECURITY_HOLE, port:port, extra:report);
}
else audit(AUDIT_HOST_NOT, "an affected model");