Vulnerabilities > CVE-2015-0676 - Improper Input Validation vulnerability in Cisco Adaptive Security Appliance Software

047910
CVSS 0.0 - NONE
Attack vector
UNKNOWN
Attack complexity
UNKNOWN
Privileges required
UNKNOWN
Confidentiality impact
UNKNOWN
Integrity impact
UNKNOWN
Availability impact
UNKNOWN

Summary

The DNS implementation in Cisco Adaptive Security Appliance (ASA) Software 7.2 before 7.2(5.16), 8.2 before 8.2(5.57), 8.3 before 8.3(2.44), 8.4 before 8.4(7.28), 8.5 before 8.5(1.24), 8.6 before 8.6(1.17), 8.7 before 8.7(1.16), 9.0 before 9.0(4.33), 9.1 before 9.1(6.1), 9.2 before 9.2(3.4), and 9.3 before 9.3(3) allows man-in-the-middle attackers to cause a denial of service (memory consumption or device outage) by triggering outbound DNS queries and then sending crafted responses to these queries, aka Bug ID CSCuq77655.

Vulnerable Configurations

Part Description Count
OS
Cisco
241

Common Weakness Enumeration (CWE)

Common Attack Pattern Enumeration and Classification (CAPEC)

  • Buffer Overflow via Environment Variables
    This attack pattern involves causing a buffer overflow through manipulation of environment variables. Once the attacker finds that they can modify an environment variable, they may try to overflow associated buffers. This attack leverages implicit trust often placed in environment variables.
  • Server Side Include (SSI) Injection
    An attacker can use Server Side Include (SSI) Injection to send code to a web application that then gets executed by the web server. Doing so enables the attacker to achieve similar results to Cross Site Scripting, viz., arbitrary code execution and information disclosure, albeit on a more limited scale, since the SSI directives are nowhere near as powerful as a full-fledged scripting language. Nonetheless, the attacker can conveniently gain access to sensitive files, such as password files, and execute shell commands.
  • Cross Zone Scripting
    An attacker is able to cause a victim to load content into their web-browser that bypasses security zone controls and gain access to increased privileges to execute scripting code or other web objects such as unsigned ActiveX controls or applets. This is a privilege elevation attack targeted at zone-based web-browser security. In a zone-based model, pages belong to one of a set of zones corresponding to the level of privilege assigned to that page. Pages in an untrusted zone would have a lesser level of access to the system and/or be restricted in the types of executable content it was allowed to invoke. In a cross-zone scripting attack, a page that should be assigned to a less privileged zone is granted the privileges of a more trusted zone. This can be accomplished by exploiting bugs in the browser, exploiting incorrect configuration in the zone controls, through a cross-site scripting attack that causes the attackers' content to be treated as coming from a more trusted page, or by leveraging some piece of system functionality that is accessible from both the trusted and less trusted zone. This attack differs from "Restful Privilege Escalation" in that the latter correlates to the inadequate securing of RESTful access methods (such as HTTP DELETE) on the server, while cross-zone scripting attacks the concept of security zones as implemented by a browser.
  • Cross Site Scripting through Log Files
    An attacker may leverage a system weakness where logs are susceptible to log injection to insert scripts into the system's logs. If these logs are later viewed by an administrator through a thin administrative interface and the log data is not properly HTML encoded before being written to the page, the attackers' scripts stored in the log will be executed in the administrative interface with potentially serious consequences. This attack pattern is really a combination of two other attack patterns: log injection and stored cross site scripting.
  • Command Line Execution through SQL Injection
    An attacker uses standard SQL injection methods to inject data into the command line for execution. This could be done directly through misuse of directives such as MSSQL_xp_cmdshell or indirectly through injection of data into the database that would be interpreted as shell commands. Sometime later, an unscrupulous backend application (or could be part of the functionality of the same application) fetches the injected data stored in the database and uses this data as command line arguments without performing proper validation. The malicious data escapes that data plane by spawning new commands to be executed on the host.

Nessus

NASL familyCISCO
NASL idCISCO-SA-20150408-ASA.NASL
descriptionThe remote Cisco Adaptive Security Appliance (ASA) is missing a vendor-supplied security patch and is therefore affected by the following vulnerabilities : - A flaw exists in the failover ipsec feature due to not properly handling failover communication messages. An unauthenticated attacker, sending crafted UDP packets over the local network to the failover interface, can reconfigure the failover units to gain full control. (CVE-2015-0675) - A flaw exists when handling DNS reply packets, which a man-in-the-middle attacker, by triggering outbound DNS queries and then sending crafted responses to these, can exploit to consume excessive memory, leading to a denial of service. (CVE-2015-0676) - A flaw exists in the XML Parser configuration when handling specially crafted XML messages, which a remote, unauthenticated attacker can use to crash the WebVPN component, resulting in a denial of service condition. (CVE-2015-0677)
last seen2020-06-01
modified2020-06-02
plugin id82852
published2015-04-17
reporterThis script is Copyright (C) 2015-2019 and is owned by Tenable, Inc. or an Affiliate thereof.
sourcehttps://www.tenable.com/plugins/nessus/82852
titleCisco ASA Software Multiple Vulnerabilities (cisco-sa-20150408-asa)
code
#TRUSTED 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
#
# (C) Tenable Network Security, Inc.
#

include("compat.inc");

if (description)
{
  script_id(82852);
  script_version("1.11");
  script_cvs_date("Date: 2019/11/22");

  script_cve_id("CVE-2015-0675", "CVE-2015-0676", "CVE-2015-0677");
  script_bugtraq_id(73966, 73967, 73969);
  script_xref(name:"CISCO-BUG-ID", value:"CSCuq77655");
  script_xref(name:"CISCO-BUG-ID", value:"CSCus95290");
  script_xref(name:"CISCO-BUG-ID", value:"CSCur21069");
  script_xref(name:"CISCO-SA", value:"cisco-sa-20150408-asa");

  script_name(english:"Cisco ASA Software Multiple Vulnerabilities (cisco-sa-20150408-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:
"The remote Cisco Adaptive Security Appliance (ASA) is missing a
vendor-supplied security patch and is therefore affected by the
following vulnerabilities :

  - A flaw exists in the failover ipsec feature due to not
    properly handling failover communication messages. An
    unauthenticated attacker, sending crafted UDP packets
    over the local network to the failover interface, can
    reconfigure the failover units to gain full control.
    (CVE-2015-0675)

  - A flaw exists when handling DNS reply packets, which a
    man-in-the-middle attacker, by triggering outbound DNS
    queries and then sending crafted responses to these, can
    exploit to consume excessive memory, leading to a denial
    of service. (CVE-2015-0676)

  - A flaw exists in the XML Parser configuration when
    handling specially crafted XML messages, which a remote,
    unauthenticated attacker can use to crash the WebVPN
    component, resulting in a denial of service condition.
    (CVE-2015-0677)");
  # https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20150408-asa
  script_set_attribute(attribute:"see_also", value:"http://www.nessus.org/u?0ddbeb92");
  script_set_attribute(attribute:"solution", value:
"Apply the relevant patch or workaround referenced in Cisco Security
Advisory cisco-sa-20150408-asa.");
  script_set_cvss_base_vector("CVSS2#AV:A/AC:L/Au:N/C:C/I:C/A:C");
  script_set_cvss_temporal_vector("CVSS2#E:U/RL:OF/RC:C");

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

  script_set_attribute(attribute:"vuln_publication_date", value:"2015/04/08");
  script_set_attribute(attribute:"patch_publication_date", value:"2015/04/08");
  script_set_attribute(attribute:"plugin_publication_date", value:"2015/04/17");

  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) 2015-2019 and is owned by Tenable, Inc. or an Affiliate thereof.");

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

  exit(0);
}

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

asa = get_kb_item_or_exit('Host/Cisco/ASA');
model = get_kb_item_or_exit('Host/Cisco/ASA/model');
ver = extract_asa_version(asa);
if (isnull(ver)) audit(AUDIT_FN_FAIL, 'extract_asa_version');

if (
  model !~ '^55[0-9][0-9]($|[^0-9])' &&
  model !~ '^65[0-9][0-9]($|[^0-9])' &&
  model !~ '^76[0-9][0-9]($|[^0-9])' &&
  model !~ '^1000V' &&
  model != 'v' # reported by ASAv
) audit(AUDIT_HOST_NOT, "ASA 5500 5000-X 6500 7600 1000V or ASAv");

flag = 0;
override = 0;
local_check = 0;
fixed_ver = "";
report = "";
report_extras = "";

# For each vulnerability, check for affected OS versions,
# set "fixed" os version, and perform any additional checks

# Determine if additional local checks can be performed
if (get_kb_item("Host/local_checks_enabled")) local_check = 1;

# #################################################
cbi = "CSCur21069";
# #################################################
temp_flag = 0;

if (ver =~ "^9\.1[^0-9]" && check_asa_release(version:ver, patched:"9.1(6)"))
{
  temp_flag++;
  fixed_ver = "9.1(6)";
}
else if (ver =~ "^9\.2[^0-9]" && check_asa_release(version:ver, patched:"9.2(3.3)"))
{
  temp_flag++;
  fixed_ver = "9.2(3.3)";
}
else if (ver =~ "^9\.3[^0-9]" && check_asa_release(version:ver, patched:"9.3(3)"))
{
  temp_flag++;
  fixed_ver = "9.3(3)";
}

# Need to check that failover is enabled
# as well as the failover ipsec feature
if (local_check && temp_flag)
{
  temp_flag = 0;
  buf = cisco_command_kb_item(
    "Host/Cisco/Config/show_failover",
    "show failover"
  );
  if (check_cisco_result(buf))
  {
    if (preg(multiline:TRUE, pattern:"Failover On", string:buf))
    {
      buf = NULL;
      buf = cisco_command_kb_item(
        "Host/Cisco/Config/show_running-config-failover",
        "show running-config failover | include ipsec"
      );
      if (check_cisco_result(buf))
      {
        if (preg(multiline:TRUE, pattern:"failover ipsec", string:buf))
        {
          temp_flag = 1;
        }
      }
      else if (cisco_needs_enable(buf)) {temp_flag = 1; override = 1;}
    }
  }
  else if (cisco_needs_enable(buf)) {temp_flag = 1; override = 1;}
}

if (temp_flag)
{
  report +=
    '\n  Cisco bug ID      : ' + cbi +
    '\n  Installed release : ' + ver +
    '\n  Fixed release     : ' + fixed_ver + '\n';
  flag++;
}

# #################################################
cbi = "CSCus95290";
# #################################################
temp_flag = 0;

if (ver =~ "^8\.4[^0-9]" && check_asa_release(version:ver, patched:"8.4(7.28)"))
{
  temp_flag++;
  fixed_ver = "8.4(7.28)";
}
else if (ver =~ "^8\.6[0-9]" && check_asa_release(version:ver, patched:"8.6(1.17)"))
{
  temp_flag++;
  fixed_ver = "8.6(1.17)";
}
else if (ver =~ "^9\.0[^0-9]" && check_asa_release(version:ver, patched:"9.0(4.33)"))
{
  temp_flag++;
  fixed_ver = "9.0(4.33)";
}
else if (ver =~ "^9\.1[^0-9]" && check_asa_release(version:ver, patched:"9.1(6)"))
{
  temp_flag++;
  fixed_ver = "9.1(6)";
}
else if (ver =~ "^9\.2[^0-9]" && check_asa_release(version:ver, patched:"9.2(3.4)"))
{
  temp_flag++;
  fixed_ver = "9.2(3.4)";
}
else if (ver =~ "^9\.3[^0-9]" && check_asa_release(version:ver, patched:"9.3(3)"))
{
  temp_flag++;
  fixed_ver = "9.3(3)";
}

# Need to check for AnyConnect or clientless ssl vpn
# or anyconnect IKEv2 VPN
if (local_check)
{
  if (temp_flag)
  {
    temp_flag = 0;
    # Check for ikev2 enabled
    buf1 = cisco_command_kb_item(
      "Host/Cisco/Config/show_running-config-crypto-ikev2",
      "show running-config crypto ikev2 | include enable"
    );
    buf2 = cisco_command_kb_item(
      "Host/Cisco/Config/show_running-config-webvpn",
      "show running-config webvpn"
    );
    if (check_cisco_result(buf1))
    {
      if (preg(multiline:TRUE, pattern:"crypto ikev2 enable", string:buf1))
      {
        temp_flag = 1;
      }
    }
    else if (check_cisco_result(buf2))
    {
      if (preg(multiline:TRUE, pattern:"webvpn\senable", string:buf2))
      {
        temp_flag = 1;
      }
    }
    else if (cisco_needs_enable(buf1) || cisco_needs_enable(buf2))
    {
      temp_flag = 1;
      override = 1;
    }
  }
}

if (temp_flag)
{
  report +=
    '\n  Cisco bug ID      : ' + cbi +
    '\n  Installed release : ' + ver +
    '\n  Fixed release     : ' + fixed_ver + '\n';
  flag++;
}

# #################################################
cbi = "CSCuq77655";
# #################################################
temp_flag = 0;

if (ver =~ "^7\.2[^0-9]" && check_asa_release(version:ver, patched:"7.2(5.16)"))
{
  temp_flag++;
  fixed_ver = "7.2(5.16)";
}
else if (ver =~ "^8\.2[^0-9]" && check_asa_release(version:ver, patched:"8.2(5.57)"))
{
  temp_flag++;
  fixed_ver = "8.2(5.57)";
}
else if (ver =~ "^8\.3[^0-9]" && check_asa_release(version:ver, patched:"8.3(2.44)"))
{
  temp_flag++;
  fixed_ver = "8.3(2.44)";
}
else if (ver =~ "^8\.4[^0-9]" && check_asa_release(version:ver, patched:"8.4(7.28)"))
{
  temp_flag++;
  fixed_ver = "8.4(7.28)";
}
else if (ver =~ "^8\.5[^0-9]" && check_asa_release(version:ver, patched:"8.5(1.24)"))
{
  temp_flag++;
  fixed_ver = "8.5(1.24)";
}
else if (ver =~ "^8\.6[^0-9]" && check_asa_release(version:ver, patched:"8.6(1.17)"))
{
  temp_flag++;
  fixed_ver = "8.6(1.17)";
}
else if (ver =~ "^8\.7[^0-9]" && check_asa_release(version:ver, patched:"8.7(1.16)"))
{
  temp_flag++;
  fixed_ver = "8.7(1.16)";
}
else if (ver =~ "^9\.0[^0-9]" && check_asa_release(version:ver, patched:"9.0(4.33)"))
{
  temp_flag++;
  fixed_ver = "9.0(4.33)";
}
else if (ver =~ "^9\.1[^0-9]" && check_asa_release(version:ver, patched:"9.1(6.1)"))
{
  temp_flag++;
  fixed_ver = "9.1(6.1)";
}
else if (ver =~ "^9\.2[^0-9]" && check_asa_release(version:ver, patched:"9.2(3.4)"))
{
  temp_flag++;
  fixed_ver = "9.2(3.4)";
}
else if (ver =~ "^9\.3[^0-9]" && check_asa_release(version:ver, patched:"9.3(3)"))
{
  temp_flag++;
  fixed_ver = "9.3(3)";
}

# Need to that a dns server is configured
# under a DNS server group
if (local_check)
{
  if (temp_flag)
  {
    temp_flag = 0;
    buf = cisco_command_kb_item(
      "Host/Cisco/Config/show_running-config_dns_server-group",
      "show running-config dns server-group"
    );
    if (check_cisco_result(buf))
    {
      if (preg(multiline:TRUE, icase:TRUE, pattern:"name-server\s([0-9]+\.){3}[0-9]+", string:buf))
        temp_flag = 1;
    }
    else if (cisco_needs_enable(buf)) {temp_flag = 1; override = 1;}
  }
}

if (temp_flag)
{
  report +=
    '\n  Cisco bug ID      : ' + cbi +
    '\n  Installed release : ' + ver +
    '\n  Fixed release     : ' + fixed_ver + '\n';
  flag++;
}


if (flag)
{
  security_hole(port:0, extra:report + cisco_caveat(override));
  exit(0);
}
else audit(AUDIT_HOST_NOT, "affected");