Vulnerabilities > CVE-2018-1157 - Resource Exhaustion vulnerability in Mikrotik Routeros

047910
CVSS 6.5 - MEDIUM
Attack vector
NETWORK
Attack complexity
LOW
Privileges required
LOW
Confidentiality impact
NONE
Integrity impact
NONE
Availability impact
HIGH
network
low complexity
mikrotik
CWE-400
nessus
NVD
Published: 2018-08-23
Updated: 2024-11-21

Summary

Mikrotik RouterOS before 6.42.7 and 6.40.9 is vulnerable to a memory exhaustion vulnerability. An authenticated remote attacker can crash the HTTP server and in some circumstances reboot the system via a crafted HTTP POST request.

Vulnerable Configurations

Part Description Count
OS
Mikrotik
490

Common Weakness Enumeration (CWE)

Common Attack Pattern Enumeration and Classification (CAPEC)

  • XML Ping of the Death
    An attacker initiates a resource depletion attack where a large number of small XML messages are delivered at a sufficiently rapid rate to cause a denial of service or crash of the target. Transactions such as repetitive SOAP transactions can deplete resources faster than a simple flooding attack because of the additional resources used by the SOAP protocol and the resources necessary to process SOAP messages. The transactions used are immaterial as long as they cause resource utilization on the target. In other words, this is a normal flooding attack augmented by using messages that will require extra processing on the target.
  • XML Entity Expansion
    An attacker submits an XML document to a target application where the XML document uses nested entity expansion to produce an excessively large output XML. XML allows the definition of macro-like structures that can be used to simplify the creation of complex structures. However, this capability can be abused to create excessive demands on a processor's CPU and memory. A small number of nested expansions can result in an exponential growth in demands on memory.
  • Inducing Account Lockout
    An attacker leverages the security functionality of the system aimed at thwarting potential attacks to launch a denial of service attack against a legitimate system user. Many systems, for instance, implement a password throttling mechanism that locks an account after a certain number of incorrect log in attempts. An attacker can leverage this throttling mechanism to lock a legitimate user out of their own account. The weakness that is being leveraged by an attacker is the very security feature that has been put in place to counteract attacks.
  • Violating Implicit Assumptions Regarding XML Content (aka XML Denial of Service (XDoS))
    XML Denial of Service (XDoS) can be applied to any technology that utilizes XML data. This is, of course, most distributed systems technology including Java, .Net, databases, and so on. XDoS is most closely associated with web services, SOAP, and Rest, because remote service requesters can post malicious XML payloads to the service provider designed to exhaust the service provider's memory, CPU, and/or disk space. The main weakness in XDoS is that the service provider generally must inspect, parse, and validate the XML messages to determine routing, workflow, security considerations, and so on. It is exactly these inspection, parsing, and validation routines that XDoS targets. There are three primary attack vectors that XDoS can navigate Target CPU through recursion: attacker creates a recursive payload and sends to service provider Target memory through jumbo payloads: service provider uses DOM to parse XML. DOM creates in memory representation of XML document, but when document is very large (for example, north of 1 Gb) service provider host may exhaust memory trying to build memory objects. XML Ping of death: attack service provider with numerous small files that clog the system. All of the above attacks exploit the loosely coupled nature of web services, where the service provider has little to no control over the service requester and any messages the service requester sends.

Nessus

NASL familyMisc.
NASL idMIKROTIK_AUG_2018.NASL
descriptionAccording to its self-reported version, the remote networking device is running a version of MikroTik prior to 6.40.9, 6.41.x < 6.42.7, or 6.43. It, therefore, vulnerable to multiple vulnerabilities.
last seen2020-06-01
modified2020-06-02
plugin id112114
published2018-08-24
reporterThis script is Copyright (C) 2018-2019 and is owned by Tenable, Inc. or an Affiliate thereof.
sourcehttps://www.tenable.com/plugins/nessus/112114
titleMikroTik RouterOS < 6.40.9 / 6.42.7 / 6.43 multiple vulnerabilities.
code
#
# (C) Tenable Network Security, Inc.
#

include("compat.inc");

if (description)
{
  script_id(112114);
  script_version("1.3");
  script_cvs_date("Date: 2019/11/04");

  script_cve_id(
    "CVE-2018-1156",
    "CVE-2018-1157",
    "CVE-2018-1158",
    "CVE-2018-1159"
  );

  script_name(english:"MikroTik RouterOS <  6.40.9 / 6.42.7 / 6.43 multiple vulnerabilities.");
  script_summary(english:"Checks RouterOS version");

  script_set_attribute(attribute:"synopsis", value:
"The remote networking device is affected by multiple vulnerabilities.");
  script_set_attribute(attribute:"description", value:
"According to its self-reported version, the remote networking device
is running a version of MikroTik prior to 6.40.9, 6.41.x <
6.42.7, or 6.43. It, therefore, vulnerable to multiple vulnerabilities.");
  # https://blog.mikrotik.com/security/security-issues-discovered-by-tenable.html
  script_set_attribute(attribute:"see_also", value:"http://www.nessus.org/u?237622b9");
  # https://forum.mikrotik.com/viewtopic.php?f=21&t=138331
  script_set_attribute(attribute:"see_also", value:"http://www.nessus.org/u?f9e2af40");
  # https://forum.mikrotik.com/viewtopic.php?f=21&t=138228
  script_set_attribute(attribute:"see_also", value:"http://www.nessus.org/u?c37b423c");
  script_set_attribute(attribute:"solution", value:
"Upgrade to MikroTik RouterOS 6.40.9 / 6.42.7 / 6.43 or later.");
  script_set_cvss_base_vector("CVSS2#AV:N/AC:L/Au:S/C:C/I:C/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:L/UI:N/S:U/C:H/I:H/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-2018-1156");

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

  script_set_attribute(attribute:"vuln_publication_date", value:"2018/08/22");
  script_set_attribute(attribute:"patch_publication_date", value:"2018/08/20");
  script_set_attribute(attribute:"plugin_publication_date", value:"2018/08/24");

  script_set_attribute(attribute:"plugin_type", value:"remote");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:mikrotik:routeros");
  script_end_attributes();

  script_category(ACT_GATHER_INFO);
  script_family(english:"Misc.");

  script_copyright(english:"This script is Copyright (C) 2018-2019 and is owned by Tenable, Inc. or an Affiliate thereof.");

  script_dependencies("mikrotik_detect.nasl");
  script_require_keys("MikroTik/RouterOS/Version");

  exit(0);
}

include("vcf.inc");
include("audit.inc");

app = "MikroTik";
kb_ver = "MikroTik/RouterOS/Version";
# The version can be NULL when only SSH service is running.
version = get_kb_item_or_exit(kb_ver);
if(empty_or_null(version)) audit(AUDIT_UNKNOWN_APP_VER, app);

app_info = vcf::get_app_info(app:app, kb_ver:kb_ver, service:FALSE);

constraints = [{ "fixed_version" : "6.40.9" },
               { "min_version" : "6.41", "fixed_version" : "6.42.7" }];

vcf::check_version_and_report(app_info:app_info, constraints:constraints, severity:SECURITY_HOLE, strict:FALSE);

The Hacker News

idTHN:15F5633BC0BA0C82579744CCACA99558
last seen2018-10-08
modified2018-10-08
published2018-10-08
reporterThe Hacker News
sourcehttps://thehackernews.com/2018/10/router-hacking-exploit.html
titleNew Exploit for MikroTik Router WinBox Vulnerability Gives Full Root Access

References