Vulnerabilities > CVE-2018-0470 - Improper Restriction of Operations within the Bounds of a Memory Buffer vulnerability in Cisco IOS XE 16.2.0/16.3(1)

047910
CVSS 8.6 - HIGH
Attack vector
NETWORK
Attack complexity
LOW
Privileges required
NONE
Confidentiality impact
NONE
Integrity impact
NONE
Availability impact
HIGH
network
low complexity
cisco
CWE-119
nessus

Summary

A vulnerability in the web framework of Cisco IOS XE Software could allow an unauthenticated, remote attacker to cause a buffer overflow condition on an affected device, resulting in a denial of service (DoS) condition. The vulnerability is due to the affected software improperly parsing malformed HTTP packets that are destined to a device. An attacker could exploit this vulnerability by sending a malformed HTTP packet to an affected device for processing. A successful exploit could allow the attacker to cause a buffer overflow condition on the affected device, resulting in a DoS condition.

Vulnerable Configurations

Part Description Count
OS
Cisco
2

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.
  • Overflow Buffers
    Buffer Overflow attacks target improper or missing bounds checking on buffer operations, typically triggered by input injected by an attacker. As a consequence, an attacker is able to write past the boundaries of allocated buffer regions in memory, causing a program crash or potentially redirection of execution as per the attackers' choice.
  • Client-side Injection-induced Buffer Overflow
    This type of attack exploits a buffer overflow vulnerability in targeted client software through injection of malicious content from a custom-built hostile service.
  • Filter Failure through Buffer Overflow
    In this attack, the idea is to cause an active filter to fail by causing an oversized transaction. An attacker may try to feed overly long input strings to the program in an attempt to overwhelm the filter (by causing a buffer overflow) and hoping that the filter does not fail securely (i.e. the user input is let into the system unfiltered).
  • MIME Conversion
    An attacker exploits a weakness in the MIME conversion routine to cause a buffer overflow and gain control over the mail server machine. The MIME system is designed to allow various different information formats to be interpreted and sent via e-mail. Attack points exist when data are converted to MIME compatible format and back.

Nessus

NASL familyCISCO
NASL idCISCO-SA-20180926-WEBDOS.NASL
descriptionAccording to its self-reported version, the IOS XE is affected by one or more vulnerabilities. Please see the included Cisco BIDs and the Cisco Security Advisory for more information.
last seen2020-04-30
modified2018-10-05
plugin id117955
published2018-10-05
reporterThis script is Copyright (C) 2018-2020 and is owned by Tenable, Inc. or an Affiliate thereof.
sourcehttps://www.tenable.com/plugins/nessus/117955
titleCisco IOS XE Software HTTP DoS Vulnerability (cisco-sa-20180926-webdos)
code
#TRUSTED 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
#
# (C) Tenable Network Security, Inc.
#

include("compat.inc");

if (description)
{
  script_id(117955);
  script_version("1.8");
  script_set_attribute(attribute:"plugin_modification_date", value:"2020/04/27");

  script_cve_id("CVE-2018-0470");
  script_xref(name:"CISCO-BUG-ID", value:"CSCvb22618");
  script_xref(name:"CISCO-SA", value:"cisco-sa-20180926-webdos");

  script_name(english:"Cisco IOS XE Software HTTP DoS Vulnerability (cisco-sa-20180926-webdos)");
  script_summary(english:"Checks the IOS XE 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 self-reported version, the IOS XE is affected
by one or more vulnerabilities. Please see the included Cisco BIDs
and the Cisco Security Advisory for more information.");
  # https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20180926-webdos
  script_set_attribute(attribute:"see_also", value:"http://www.nessus.org/u?1fa07425");
  script_set_attribute(attribute:"see_also", value:"https://bst.cloudapps.cisco.com/bugsearch/bug/CSCvb22618");
  script_set_attribute(attribute:"solution", value:
"Upgrade to the relevant fixed version referenced in Cisco bug ID(s)
CSCvb22618.");
  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_cvss3_base_vector("CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H");
  script_set_cvss3_temporal_vector("CVSS:3.0/E:U/RL:O/RC:C");
  script_set_attribute(attribute:"cvss_score_source", value:"CVE-2018-0470");

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

  script_set_attribute(attribute:"vuln_publication_date", value:"2018/09/26");
  script_set_attribute(attribute:"patch_publication_date", value:"2018/09/26");
  script_set_attribute(attribute:"plugin_publication_date", value:"2018/10/05");

  script_set_attribute(attribute:"plugin_type", value:"local");
  script_set_attribute(attribute:"cpe", value:"cpe:/o: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) 2018-2020 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_workarounds.inc");
include("ccf.inc");

product_info = cisco::get_product_info(name:"Cisco IOS XE Software");

version_list = make_list(
  "16.1.1",
  "16.1.2",
  "16.1.3",
  "3.2.0JA",
  "16.2.1",
  "16.2.2",
  "16.3.1",
  "16.3.2",
  "16.3.3",
  "16.3.1a",
  "16.3.4",
  "16.3.5",
  "16.3.5b",
  "16.3.6",
  "16.4.1",
  "16.4.2",
  "16.4.3",
  "16.5.1",
  "16.5.1a",
  "16.5.1b",
  "16.5.2",
  "16.5.3",
  "16.9.1b",
  "16.9.1h"
  );

workarounds = make_list(CISCO_WORKAROUNDS['HTTP_Server_iosxe']);
workaround_params = make_list();

reporting = make_array(
  'port'     , 0,
  'severity' , SECURITY_HOLE,
  'version'  , product_info['version'],
  'bug_id'   , "CSCvb22618",
  'cmds'     , make_list("show running-config")
);

cisco::check_and_report(product_info:product_info, workarounds:workarounds, workaround_params:workaround_params, reporting:reporting, vuln_versions:version_list);