Vulnerabilities > CVE-2015-6279 - Improper Input Validation vulnerability in Cisco IOS and IOS XE

047910
CVSS 7.8 - HIGH
Attack vector
NETWORK
Attack complexity
LOW
Privileges required
NONE
Confidentiality impact
NONE
Integrity impact
NONE
Availability impact
COMPLETE
network
low complexity
cisco
CWE-20
nessus
NVD
Published: 2015-09-28
Updated: 2016-12-12

Summary

The IPv6 snooping functionality in the first-hop security subsystem in Cisco IOS 12.2, 15.0, 15.1, 15.2, 15.3, 15.4, and 15.5 and IOS XE 3.2SE, 3.3SE, 3.3XO, 3.4SG, 3.5E, and 3.6E before 3.6.3E; 3.7E before 3.7.2E; 3.9S and 3.10S before 3.10.6S; 3.11S before 3.11.4S; 3.12S and 3.13S before 3.13.3S; and 3.14S before 3.14.2S allows remote attackers to cause a denial of service (device reload) via a malformed ND packet with the Cryptographically Generated Address (CGA) option, aka Bug ID CSCuo04400.

Vulnerable Configurations

Part Description Count
OS
Cisco
139

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-20150923-FHS-IOS.NASL
    descriptionThe remote Cisco IOS device missing vendor-supplied security patches, and is configured for IPv6 snooping. It is, therefore, affected by the following vulnerabilities : - A flaw exists in the IPv6 Snooping feature due to missing Control Plane Protection (CPPr) protection mechanisms. An unauthenticated, remote attacker can exploit this to cause a saturation of IPv6 ND packets, resulting in a reboot of the device. (CVE-2015-6278) - A flaw exists in the IPv6 Snooping feature due to improper validation of IPv6 ND packets that use the Cryptographically Generated Address (CGA) option. An unauthenticated, remote attacker can exploit this, via a malformed package, to cause a saturation of IPv6 ND packets, resulting in a device reboot. (CVE-2015-6279)
    last seen2019-10-28
    modified2015-10-02
    plugin id86246
    published2015-10-02
    reporterThis script is Copyright (C) 2015-2018 Tenable Network Security, Inc.
    sourcehttps://www.tenable.com/plugins/nessus/86246
    titleCisco IOS IPv6 Snooping DoS (cisco-sa-20150923-fhs)
    code
    #TRUSTED 354df3a268d0009f526ff8eb6ab2e52e9c8882ae64aae1003cad76e280d844ae88a6568fe8a2dfca4c68fbaddb08b774176d3c7d32e7f07c136a793aa87035833a6d5b5ed564303774517f21b8fb6506449a61f5df943526c01ab9967311226df0d0634ead3d3a785ec5db0c2a9c926831ddfabb4d4c3493888701294e7e584a933fe849c59478f5c8de6604931da14f75d6aee27ed806dc51e636d751cd1f9ead29d3ff129f2ab027c432d243f4bc32a4e4ad08b2c1016ed2f17303cd80688db2e76082c6e18acdf06cacf0c97b224a867615897b27ea7a3d07ce02779a10d1be5ec561973ade234e68514f76a78cfe5889e355163270d10ef1e97704b23563b8ef83237d7396b742ea3a9b3694079907f31f74f4856cfaa2f6960311ce98aac3deefa0067890e954251b5bbd6e74169ee17260b29fb00ed8d712147d86faffadeee2eb1220f1baf60902292b4ec8bb1e9984b4473ed39a252d283022d557b6c70fdc8d52e1f32bbcc6aa781b1660bc2c0c469aa473006cfd556f6f64efc1e8d2620c3093092c91c5b9ab4e457f057f9081adabc876a80863ff262de42c93c4aef7b94fb43de3db6cbdfcfed6ac22923f047e455cd5fe4b043d007a70cb297ebae5d7c6d5d31d27bbfda4eb7b78d61cdb77ff8fe4a6791a4662f45df973f3a7297a2874e7c271c0bb2d883e00e9ad849b4c19567a3954c47c85063d3dd7209a
#
# (C) Tenable Network Security, Inc.
#

include("compat.inc");

if (description){

  script_id(86246);
  script_version("1.10");
  script_set_attribute(attribute:"plugin_modification_date", value:"2018/11/15");

  script_cve_id("CVE-2015-6278", "CVE-2015-6279");
  script_xref(name:"CISCO-BUG-ID", value:"CSCuo04400");
  script_xref(name:"CISCO-BUG-ID", value:"CSCus19794");
  script_xref(name:"CISCO-SA", value:"cisco-sa-20150923-fhs");

  script_name(english:"Cisco IOS IPv6 Snooping DoS (cisco-sa-20150923-fhs)");
  script_summary(english:"Checks IOS version.");

  script_set_attribute(attribute:"synopsis", value:
"The remote device is missing vendor-supplied security patches.");
  script_set_attribute(attribute:"description", value:
"The remote Cisco IOS device missing vendor-supplied security patches,
and is configured for IPv6 snooping. It is, therefore, affected by the
following vulnerabilities :

  - A flaw exists in the IPv6 Snooping feature due to
    missing Control Plane Protection (CPPr) protection
    mechanisms. An unauthenticated, remote attacker can
    exploit this to cause a saturation of IPv6 ND packets,
    resulting in a reboot of the device. (CVE-2015-6278)

  - A flaw exists in the IPv6 Snooping feature due to
    improper validation of IPv6 ND packets that use the
    Cryptographically Generated Address (CGA) option. An
    unauthenticated, remote attacker can exploit this, via a
    malformed package, to cause a saturation of IPv6 ND
    packets, resulting in a device reboot. (CVE-2015-6279)");
  # https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20150923-fhs
  script_set_attribute(attribute:"see_also", value:"http://www.nessus.org/u?8c8077d4");
  script_set_attribute(attribute:"solution", value:
"Upgrade to the relevant fixed version referenced in Cisco bug IDs
CSCuo04400 and CSCus19794.

Alternatively, as a temporary workaround, disable IPv6 snooping and
SSHv2 RSA-based user authentication.");
  script_set_cvss_base_vector("CVSS2#AV:N/AC:L/Au:N/C:N/I:N/A:C");

  script_set_attribute(attribute:"vuln_publication_date", value:"2015/09/23");
  script_set_attribute(attribute:"patch_publication_date", value:"2015/09/23");
  script_set_attribute(attribute:"plugin_publication_date", value:"2015/10/02");

  script_set_attribute(attribute:"plugin_type", value:"combined");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:cisco:ios");
  script_end_attributes();

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

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

  script_dependencies("cisco_ios_version.nasl");
  script_require_keys("Host/Cisco/IOS/Version");
  exit(0);
}

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

ver = get_kb_item_or_exit("Host/Cisco/IOS/Version");

flag = 0;

if (ver =='12.2(50)SY') flag++;
if (ver =='12.2(50)SY1') flag++;
if (ver =='12.2(50)SY2') flag++;
if (ver =='12.2(50)SY3') flag++;
if (ver =='12.2(50)SY4') flag++;
if (ver =='15.0(1)EX') flag++;
if (ver =='15.0(1)SY') flag++;
if (ver =='15.0(1)SY1') flag++;
if (ver =='15.0(1)SY2') flag++;
if (ver =='15.0(1)SY3') flag++;
if (ver =='15.0(1)SY4') flag++;
if (ver =='15.0(1)SY5') flag++;
if (ver =='15.0(1)SY6') flag++;
if (ver =='15.0(1)SY7') flag++;
if (ver =='15.0(1)SY7a') flag++;
if (ver =='15.0(1)SY8') flag++;
if (ver =='15.0(2)EA2') flag++;
if (ver =='15.0(2)EJ') flag++;
if (ver =='15.0(2)EJ1') flag++;
if (ver =='15.0(2)EZ') flag++;
if (ver =='15.0(2)SE') flag++;
if (ver =='15.0(2)SE1') flag++;
if (ver =='15.0(2)SE2') flag++;
if (ver =='15.0(2)SE3') flag++;
if (ver =='15.0(2)SE4') flag++;
if (ver =='15.0(2)SE5') flag++;
if (ver =='15.0(2)SE6') flag++;
if (ver =='15.0(2)SE7') flag++;
if (ver =='15.1(1)SY') flag++;
if (ver =='15.1(1)SY1') flag++;
if (ver =='15.1(1)SY2') flag++;
if (ver =='15.1(1)SY3') flag++;
if (ver =='15.1(1)SY4') flag++;
if (ver =='15.1(1)SY5') flag++;
if (ver =='15.1(2)SG') flag++;
if (ver =='15.1(2)SG1') flag++;
if (ver =='15.1(2)SG2') flag++;
if (ver =='15.1(2)SG3') flag++;
if (ver =='15.1(2)SG4') flag++;
if (ver =='15.1(2)SG5') flag++;
if (ver =='15.1(2)SY') flag++;
if (ver =='15.1(2)SY1') flag++;
if (ver =='15.1(2)SY2') flag++;
if (ver =='15.1(2)SY3') flag++;
if (ver =='15.1(2)SY4') flag++;
if (ver =='15.1(2)SY4a') flag++;
if (ver =='15.1(2)SY5') flag++;
if (ver =='15.2(1)E') flag++;
if (ver =='15.2(1)E1') flag++;
if (ver =='15.2(1)E2') flag++;
if (ver =='15.2(1)E3') flag++;
if (ver =='15.2(1)SY') flag++;
if (ver =='15.2(1)SY0a') flag++;
if (ver =='15.2(2)E') flag++;
if (ver =='15.2(2)E1') flag++;
if (ver =='15.2(2)E2') flag++;
if (ver =='15.2(2)EA1') flag++;
if (ver =='15.2(2a)E1') flag++;
if (ver =='15.2(3)E') flag++;
if (ver =='15.2(3)E1') flag++;
if (ver =='15.2(3a)E') flag++;
if (ver =='15.2(4)S') flag++;
if (ver =='15.2(4)S1') flag++;
if (ver =='15.2(4)S2') flag++;
if (ver =='15.2(4)S3') flag++;
if (ver =='15.2(4)S3a') flag++;
if (ver =='15.2(4)S4') flag++;
if (ver =='15.2(4)S4a') flag++;
if (ver =='15.2(4)S5') flag++;
if (ver =='15.2(4)S6') flag++;
if (ver =='15.3(1)S') flag++;
if (ver =='15.3(1)S2') flag++;
if (ver =='15.3(2)S') flag++;
if (ver =='15.3(2)S0a') flag++;
if (ver =='15.3(2)S1') flag++;
if (ver =='15.3(2)S2') flag++;
if (ver =='15.3(3)S') flag++;
if (ver =='15.3(3)S1') flag++;
if (ver =='15.3(3)S2') flag++;
if (ver =='15.3(3)S3') flag++;
if (ver =='15.3(3)S4') flag++;
if (ver =='15.4(1)S') flag++;
if (ver =='15.4(1)S1') flag++;
if (ver =='15.4(1)S2') flag++;
if (ver =='15.4(1)S3') flag++;
if (ver =='15.4(2)S') flag++;
if (ver =='15.4(2)S1') flag++;
if (ver =='15.4(2)S2') flag++;
if (ver =='15.5(1)S') flag++;
if (ver =='15.5(1)S1') flag++;

if (get_kb_item("Host/local_checks_enabled") && flag)
{
  flag = 0;
  buf = cisco_command_kb_item("Host/Cisco/Config/show-ipv6-snooping-policies", "show ipv6 snooping policies");
  if (check_cisco_result(buf))
  {
    if ("Snooping" >< buf) flag = 1;
  }
  else if (cisco_needs_enable(buf))
  {
    flag = 1;
    override = 1;
  }
}

if (flag)
{
  if (report_verbosity > 0)
  {
    report =
      '\n  Cisco bug IDs     : CSCuo04400 / CSCus19794' +
      '\n  Installed release : ' + ver +
      '\n';
    security_hole(port:0, extra:report + cisco_caveat(override));
  }
  else security_hole(port:0, extra:cisco_caveat(override));
  exit(0);
}
else audit(AUDIT_HOST_NOT, "affected");
  • NASL familyCISCO
    NASL idCISCO-SA-20150923-FHS-IOSXE.NASL
    descriptionThe remote Cisco IOS XE device is missing vendor-supplied security patches, and is configured for IPv6 snooping. It is, therefore, affected by the following vulnerabilities : - A flaw exists in the IPv6 Snooping feature due to missing Control Plane Protection (CPPr) protection mechanisms. An unauthenticated, remote attacker can exploit this to cause a saturation of IPv6 ND packets, resulting in a reboot of the device. (CVE-2015-6278) - A flaw exists in the IPv6 Snooping feature due to improper validation of IPv6 ND packets that use the Cryptographically Generated Address (CGA) option. An unauthenticated, remote attacker can exploit this, via a malformed package, to cause a saturation of IPv6 ND packets, resulting in a device reboot. (CVE-2015-6279)
    last seen2020-06-01
    modified2020-06-02
    plugin id86247
    published2015-10-02
    reporterThis script is Copyright (C) 2015-2019 and is owned by Tenable, Inc. or an Affiliate thereof.
    sourcehttps://www.tenable.com/plugins/nessus/86247
    titleCisco IOS XE IPv6 Snooping DoS (cisco-sa-20150923-fhs)
    code
    #TRUSTED 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
#
# (C) Tenable Network Security, Inc.
#

include("compat.inc");

if (description)
{
  script_id(86247);
  script_version("1.13");
  script_cvs_date("Date: 2019/11/20");

  script_cve_id("CVE-2015-6278", "CVE-2015-6279");
  script_xref(name:"CISCO-BUG-ID", value:"CSCuo04400");
  script_xref(name:"CISCO-BUG-ID", value:"CSCus19794");
  script_xref(name:"CISCO-SA", value:"cisco-sa-20150923-fhs");

  script_name(english:"Cisco IOS XE IPv6 Snooping DoS (cisco-sa-20150923-fhs)");
  script_summary(english:"Checks IOS XE version.");

  script_set_attribute(attribute:"synopsis", value:
"The remote device is missing vendor-supplied security patches.");
  script_set_attribute(attribute:"description", value:
"The remote Cisco IOS XE device is missing vendor-supplied security
patches, and is configured for IPv6 snooping. It is, therefore,
affected by the following vulnerabilities :

  - A flaw exists in the IPv6 Snooping feature due to
    missing Control Plane Protection (CPPr) protection
    mechanisms. An unauthenticated, remote attacker can
    exploit this to cause a saturation of IPv6 ND packets,
    resulting in a reboot of the device. (CVE-2015-6278)

  - A flaw exists in the IPv6 Snooping feature due to
    improper validation of IPv6 ND packets that use the
    Cryptographically Generated Address (CGA) option. An
    unauthenticated, remote attacker can exploit this, via a
    malformed package, to cause a saturation of IPv6 ND
    packets, resulting in a device reboot. (CVE-2015-6279)");
  # https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20150923-fhs
  script_set_attribute(attribute:"see_also", value:"http://www.nessus.org/u?8c8077d4");
  script_set_attribute(attribute:"solution", value:
"Upgrade to the relevant fixed version referenced in Cisco bug IDs
CSCuo04400 and CSCus19794.

Alternatively, as a temporary workaround, disable IPv6 snooping and
SSHv2 RSA-based user authentication.");
  script_set_cvss_base_vector("CVSS2#AV:N/AC:L/Au:N/C:N/I:N/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:"2015/09/23");
  script_set_attribute(attribute:"patch_publication_date", value:"2015/09/23");
  script_set_attribute(attribute:"plugin_publication_date", value:"2015/10/02");

  script_set_attribute(attribute:"plugin_type", value:"local");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:cisco:ios_xe");
  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("cisco_ios_xe_version.nasl");
  script_require_keys("Host/Cisco/IOS-XE/Version");

  exit(0);
}

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

version = get_kb_item_or_exit("Host/Cisco/IOS-XE/Version");

flag     = FALSE;
override = FALSE;

if (version =='3.2.0SE') flag++;
if (version =='3.2.1SE') flag++;
if (version =='3.2.2SE') flag++;
if (version =='3.2.3SE') flag++;
if (version =='3.3.0SE') flag++;
if (version =='3.3.0XO') flag++;
if (version =='3.3.1SE') flag++;
if (version =='3.3.1XO') flag++;
if (version =='3.3.2SE') flag++;
if (version =='3.3.2XO') flag++;
if (version =='3.3.3SE') flag++;
if (version =='3.3.4SE') flag++;
if (version =='3.3.5SE') flag++;
if (version =='3.4.0SG') flag++;
if (version =='3.4.1SG') flag++;
if (version =='3.4.2SG') flag++;
if (version =='3.4.3SG') flag++;
if (version =='3.4.4SG') flag++;
if (version =='3.4.5SG') flag++;
if (version =='3.4.6SG') flag++;
if (version =='3.5.0E') flag++;
if (version =='3.5.1E') flag++;
if (version =='3.5.2E') flag++;
if (version =='3.5.3E') flag++;
if (version =='3.6.0E') flag++;
if (version =='3.6.0aE') flag++;
if (version =='3.6.0bE') flag++;
if (version =='3.6.1E') flag++;
if (version =='3.6.2E') flag++;
if (version =='3.6.2aE') flag++;
if (version =='3.7.0E') flag++;
if (version =='3.7.1E') flag++;
if (version =='3.9.0S') flag++;
if (version =='3.9.1S') flag++;
if (version =='3.9.2S') flag++;
if (version =='3.10.01S') flag++;
if (version =='3.10.0S') flag++;
if (version =='3.10.0aS') flag++;
if (version =='3.10.1S') flag++;
if (version =='3.10.2S') flag++;
if (version =='3.10.3S') flag++;
if (version =='3.10.4S') flag++;
if (version =='3.10.5S') flag++;
if (version =='3.11.0S') flag++;
if (version =='3.11.1S') flag++;
if (version =='3.11.2S') flag++;
if (version =='3.11.3S') flag++;
if (version =='3.12.0S') flag++;
if (version =='3.12.1S') flag++;
if (version =='3.12.2S') flag++;
if (version =='3.12.3S') flag++;
if (version =='3.13.0S') flag++;
if (version =='3.13.1S') flag++;
if (version =='3.13.2S') flag++;
if (version =='3.14.0S') flag++;
if (version =='3.14.1S') flag++;

if (!flag)
  audit(AUDIT_INST_VER_NOT_VULN, "Cisco IOS XE software", version);

if (get_kb_item("Host/local_checks_enabled"))
{
  flag = FALSE;
  buf = cisco_command_kb_item("Host/Cisco/Config/show-ipv6-snooping-policies", "show ipv6 snooping policies");
  if (check_cisco_result(buf))
  {
    if ("Snooping" >< 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  Cisco bug IDs     : CSCuo04400 / CSCus19794' +
    '\n  Installed release : ' + version +
    '\n';
  security_hole(port:0, extra:report+cisco_caveat(override));
}
else security_hole(port:0, extra:cisco_caveat(override));

References