Vulnerabilities > CVE-2016-1295 - Information Exposure vulnerability in Cisco Adaptive Security Appliance Software

047910
CVSS 5.3 - MEDIUM
Attack vector
NETWORK
Attack complexity
LOW
Privileges required
NONE
Confidentiality impact
LOW
Integrity impact
NONE
Availability impact
NONE
network
low complexity
cisco
CWE-200
nessus
NVD
Published: 2016-01-16
Updated: 2023-08-15

Summary

Cisco Adaptive Security Appliance (ASA) Software 8.4 allows remote attackers to obtain sensitive information via an AnyConnect authentication attempt, aka Bug ID CSCuo65775.

Vulnerable Configurations

Part Description Count
OS
Cisco
26

Common Weakness Enumeration (CWE)

Common Attack Pattern Enumeration and Classification (CAPEC)

  • Subverting Environment Variable Values
    The attacker directly or indirectly modifies environment variables used by or controlling the target software. The attacker's goal is to cause the target software to deviate from its expected operation in a manner that benefits the attacker.
  • Footprinting
    An attacker engages in probing and exploration activity to identify constituents and properties of the target. Footprinting is a general term to describe a variety of information gathering techniques, often used by attackers in preparation for some attack. It consists of using tools to learn as much as possible about the composition, configuration, and security mechanisms of the targeted application, system or network. Information that might be collected during a footprinting effort could include open ports, applications and their versions, network topology, and similar information. While footprinting is not intended to be damaging (although certain activities, such as network scans, can sometimes cause disruptions to vulnerable applications inadvertently) it may often pave the way for more damaging attacks.
  • 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.
  • Browser Fingerprinting
    An attacker carefully crafts small snippets of Java Script to efficiently detect the type of browser the potential victim is using. Many web-based attacks need prior knowledge of the web browser including the version of browser to ensure successful exploitation of a vulnerability. Having this knowledge allows an attacker to target the victim with attacks that specifically exploit known or zero day weaknesses in the type and version of the browser used by the victim. Automating this process via Java Script as a part of the same delivery system used to exploit the browser is considered more efficient as the attacker can supply a browser fingerprinting method and integrate it with exploit code, all contained in Java Script and in response to the same web page request by the browser.
  • Session Credential Falsification through Prediction
    This attack targets predictable session ID in order to gain privileges. The attacker can predict the session ID used during a transaction to perform spoofing and session hijacking.

Nessus

  • NASL familyCISCO
    NASL idCISCO-SA-20160115-ASA.NASL
    descriptionAccording to its version and configuration, the Cisco Adaptive Security Appliance (ASA) software running on the remote device is affected by an information disclosure vulnerability due to a failure to protect sensitive data during a Cisco AnyConnect client authentication attempt. An unauthenticated, remote attacker can exploit this, by attempting to authenticate to the Cisco ASA with AnyConnect, to disclose sensitive data, including the ASA software version Note that the SSL VPN feature must be enabled for the device to be affected by this vulnerability.
    last seen2020-06-01
    modified2020-06-02
    plugin id91962
    published2016-07-06
    reporterThis script is Copyright (C) 2016-2019 and is owned by Tenable, Inc. or an Affiliate thereof.
    sourcehttps://www.tenable.com/plugins/nessus/91962
    titleCisco ASA AnyConnect Client Authentication Attempt Handling Information Disclosure (cisco-sa-20160115-asa)
    code
    #TRUSTED 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
#
# (C) Tenable Network Security, Inc.
#

include("compat.inc");

if (description)
{
  script_id(91962);
  script_version("1.10");
  script_cvs_date("Date: 2019/11/19");

  script_cve_id("CVE-2016-1295");
  script_xref(name:"CISCO-BUG-ID", value:"CSCuo65775");
  script_xref(name:"CISCO-SA", value:"cisco-sa-20160115-asa");

  script_name(english:"Cisco ASA AnyConnect Client Authentication Attempt Handling Information Disclosure (cisco-sa-20160115-asa)");
  script_summary(english:"Checks the ASA version.");

  script_set_attribute(attribute:"synopsis", value:
"The remote device is missing a vendor-supplied security patch.");
  script_set_attribute(attribute:"description", value:
"According to its version and configuration, the Cisco Adaptive
Security Appliance (ASA) software running on the remote device is
affected by an information disclosure vulnerability due to a failure
to protect sensitive data during a Cisco AnyConnect client
authentication attempt. An unauthenticated, remote attacker can
exploit this, by attempting to authenticate to the Cisco ASA with
AnyConnect, to disclose sensitive data, including the ASA software
version

Note that the SSL VPN feature must be enabled for the device to be
affected by this vulnerability.");
  # https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20160115-asa
  script_set_attribute(attribute:"see_also", value:"http://www.nessus.org/u?408d7839");
  script_set_attribute(attribute:"solution", value:
"Upgrade to the relevant fixed version referenced in Cisco bug ID
CSCuo65775.");
  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:OF/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:O/RC:C");
  script_set_attribute(attribute:"cvss_score_source", value:"CVE-2016-1295");

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

  script_set_attribute(attribute:"vuln_publication_date", value:"2016/01/15");
  script_set_attribute(attribute:"patch_publication_date", value:"2016/06/27");
  script_set_attribute(attribute:"plugin_publication_date", value:"2016/07/06");

  script_set_attribute(attribute:"plugin_type", value:"local");
  script_set_attribute(attribute:"cpe", value:"cpe:/a:cisco:adaptive_security_appliance_software");
  script_end_attributes();

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

  script_copyright(english:"This script is Copyright (C) 2016-2019 and is owned by Tenable, Inc. or an Affiliate thereof.");

  script_dependencies("ssh_get_info.nasl");
  script_require_keys("Host/Cisco/ASA");

  exit(0);
}

include("audit.inc");
include("cisco_func.inc");
include("cisco_kb_cmd_func.inc");

asa   = get_kb_item_or_exit('Host/Cisco/ASA');

ver = extract_asa_version(asa);
if (isnull(ver)) audit(AUDIT_FN_FAIL, 'extract_asa_version');

fixed_ver = NULL;

if (ver =~ "^8\.4[^0-9]")
  fixed_ver = "Refer to vendor.";

else if (ver =~ "^9\.1[^0-9]" && check_asa_release(version:ver, patched:"9.1(6.100)"))
  fixed_ver = "9.1(6.100)";

else if (ver =~ "^9\.2[^0-9]" && check_asa_release(version:ver, patched:"9.2(4.11)"))
  fixed_ver = "9.2(4.11)";

else if (ver =~ "^9\.3[^0-9]" && check_asa_release(version:ver, patched:"9.3(1.99)"))
  fixed_ver = "9.3(1.99)";

else if (ver =~ "^9\.4[^0-9]" && check_asa_release(version:ver, patched:"9.4(0.109)"))
  fixed_ver = "9.4(0.109)";
if (isnull(fixed_ver))
  audit(AUDIT_INST_VER_NOT_VULN, "Cisco ASA software", ver);

flag     = FALSE;
override = FALSE;

# Check if SSL VPN (WebVPN) feature is enabled
if (get_kb_item("Host/local_checks_enabled"))
{
  buf = cisco_command_kb_item("Host/Cisco/Config/show_running-config_webvpn", "show running-config webvpn");
  if (check_cisco_result(buf))
  {
    if (preg(multiline:TRUE, pattern:"enable", string:buf)) flag = TRUE;
  }
  else if (cisco_needs_enable(buf)) override = TRUE;
}

if (!flag && !override) audit(AUDIT_HOST_NOT, "affected");

if (report_verbosity > 0)
{
  report =
    '\n  Installed version : ' + ver +
    '\n  Fixed version     : ' + fixed_ver +
    '\n';
  security_warning(port:0, extra:report+cisco_caveat(override));
}
else security_warning(port:0, extra:cisco_caveat(override));
  • NASL familyCISCO
    NASL idCISCO_ASA_INFO_DISCLOSURE_CSCUO65775.NASL
    descriptionAccording to its version and configuration, the Cisco Adaptive Security Appliance (ASA) software running on the remote device is affected by an information disclosure vulnerability due to a failure to protect sensitive data during a Cisco AnyConnect client authentication attempt. An unauthenticated, remote attacker can exploit this, by attempting to authenticate to the Cisco ASA with AnyConnect, to disclose sensitive data, including the ASA software version. Note that the SSL VPN feature must be enabled for the device to be affected by this vulnerability.
    last seen2020-06-01
    modified2020-06-02
    plugin id91963
    published2016-07-06
    reporterThis script is Copyright (C) 2016-2019 and is owned by Tenable, Inc. or an Affiliate thereof.
    sourcehttps://www.tenable.com/plugins/nessus/91963
    titleCisco ASA AnyConnect Client Authentication Attempt Handling Information Disclosure (cisco-sa-20160115-asa)
    code
    #
# (C) Tenable Network Security, Inc.
#

include("compat.inc");

if (description)
{
  script_id(91963);
  script_version("1.5");
  script_cvs_date("Date: 2019/11/19");

  script_cve_id("CVE-2016-1295");
  script_xref(name:"CISCO-BUG-ID", value:"CSCuo65775");
  script_xref(name:"CISCO-SA", value:"cisco-sa-20160115-asa");

  script_name(english:"Cisco ASA AnyConnect Client Authentication Attempt Handling Information Disclosure (cisco-sa-20160115-asa)");
  script_summary(english:"Attempts to get the device version.");

  script_set_attribute(attribute:"synopsis", value:
"The remote device is missing a vendor-supplied security patch.");
  script_set_attribute(attribute:"description", value:
"According to its version and configuration, the Cisco Adaptive
Security Appliance (ASA) software running on the remote device is
affected by an information disclosure vulnerability due to a failure
to protect sensitive data during a Cisco AnyConnect client
authentication attempt. An unauthenticated, remote attacker can
exploit this, by attempting to authenticate to the Cisco ASA with
AnyConnect, to disclose sensitive data, including the ASA software
version.

Note that the SSL VPN feature must be enabled for the device to be
affected by this vulnerability.");
  # https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20160115-asa
  script_set_attribute(attribute:"see_also", value:"http://www.nessus.org/u?408d7839");
  script_set_attribute(attribute:"solution", value:
"Upgrade to the relevant fixed version referenced in Cisco bug ID
CSCuo65775.");
  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:OF/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:O/RC:C");
  script_set_attribute(attribute:"cvss_score_source", value:"CVE-2016-1295");

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

  script_set_attribute(attribute:"vuln_publication_date", value:"2016/01/15");
  script_set_attribute(attribute:"patch_publication_date", value:"2016/01/15");
  script_set_attribute(attribute:"plugin_publication_date", value:"2016/07/06");

  script_set_attribute(attribute:"plugin_type", value:"remote");
  script_set_attribute(attribute:"cpe", value:"cpe:/a:cisco:adaptive_security_appliance_software");
  script_end_attributes();

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

  script_copyright(english:"This script is Copyright (C) 2016-2019 and is owned by Tenable, Inc. or an Affiliate thereof.");

  script_dependencies("cisco_asa_ssl_vpn_detect.nasl");
  script_require_keys("Services/cisco-ssl-vpn-svr");
  script_require_ports("Services/www", 443);

  exit(0);
}

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

appname = "Cisco ASA";
port    = get_service(svc:"cisco-ssl-vpn-svr", default:443, exit_on_fail:TRUE);
url = '/';
header = {"X-Aggregate-Auth":1};
version = UNKNOWN_VER;

res = http_send_recv3(method:"POST", item: url, port:port, add_headers: header, data: "nessus", exit_on_fail:TRUE);

if (res[0] =~ "^HTTP/[0-9.]+ +200" && "<config-auth client=" >< res[2])
{
  # Example: <version who="sg">9.1(5)</version>
  pat = "<version [^>]+>([0-9.]+\([0-9.]+\)\d{0,2})</version>";

  matches = eregmatch(pattern:pat, string:res[2]);
  if (!isnull(matches))
  {
    version = matches[1]; 

    report = 
      '\n' + "Nessus was able to determine the remote Cisco ASA version :" +
      '\n' +
      '\n' + "  URL     : " + build_url(port:port, qs:url) + 
      '\n' + "  Version : " + version +
      '\n';
    security_report_v4(severity:SECURITY_WARNING, port:port, extra:report);
  }
  else audit(AUDIT_DEVICE_NOT_VULN, "The "+appname+" on port "+port);
}
else audit(AUDIT_DEVICE_NOT_VULN, "The "+appname+" on port "+port);

References