Vulnerabilities > CVE-2006-1652 - Buffer Errors vulnerability in Ultravnc Tabbed Viewer and VNC Viewer

047910
CVSS 9.0 - CRITICAL
Attack vector
NETWORK
Attack complexity
LOW
Privileges required
SINGLE
Confidentiality impact
COMPLETE
Integrity impact
COMPLETE
Availability impact
COMPLETE
network
low complexity
ultravnc
CWE-119
critical
nessus
exploit available
metasploit
NVD
Published: 2006-04-06
Updated: 2018-10-18

Summary

Multiple buffer overflows in (a) UltraVNC (aka Ultr@VNC) 1.0.1 and earlier and (b) tabbed_viewer 1.29 (1) allow user-assisted remote attackers to execute arbitrary code via a malicious server that sends a long string to a client that connects on TCP port 5900, which triggers an overflow in Log::ReallyPrint; and (2) allow remote attackers to cause a denial of service (server crash) via a long HTTP GET request to TCP port 5800, which triggers an overflow in VNCLog::ReallyPrint. There are two seperate vulnerabilities here; One allows escalated priveleges to authenticated users, the other allows remote unauthenticated users to cause a Denial of Service (DoS).

Vulnerable Configurations

Part Description Count
Application
Ultravnc
2

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.
  • 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.

Exploit-Db

  • descriptionUltraVNC 1.0.1 Client Buffer Overflow. CVE-2006-1652. Remote exploit for windows platform
    idEDB-ID:16490
    last seen2016-02-01
    modified2010-04-30
    published2010-04-30
    reportermetasploit
    sourcehttps://www.exploit-db.com/download/16490/
    titleUltraVNC 1.0.1 Client Buffer Overflow
  • descriptionUltraVNC 1.0.1 Multiple Remote Error Logging Buffer Overflow Vulnerabilities (2). CVE-2006-1652. Remote exploit for windows platform
    idEDB-ID:27569
    last seen2016-02-03
    modified2006-04-04
    published2006-04-04
    reporterLuigi Auriemma
    sourcehttps://www.exploit-db.com/download/27569/
    titleUltraVNC 1.0.1 - Multiple Remote Error Logging Buffer Overflow Vulnerabilities 2
  • descriptionUltraVNC 1.0.1 Multiple Remote Error Logging Buffer Overflow Vulnerabilities (1). CVE-2006-1652. Remote exploit for windows platform
    idEDB-ID:27568
    last seen2016-02-03
    modified2006-04-04
    published2006-04-04
    reporterLuigi Auriemma
    sourcehttps://www.exploit-db.com/download/27568/
    titleUltraVNC 1.0.1 - Multiple Remote Error Logging Buffer Overflow Vulnerabilities 1
  • idEDB-ID:1642
  • idEDB-ID:1643

Metasploit

descriptionThis module exploits a buffer overflow in UltraVNC Win32 Viewer 1.0.1 Release.
idMSF:EXPLOIT/WINDOWS/VNC/ULTRAVNC_CLIENT
last seen2020-06-13
modified2017-07-24
published2006-12-14
referenceshttps://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2006-1652
reporterRapid7
sourcehttps://github.com/rapid7/metasploit-framework/blob/master//modules/exploits/windows/vnc/ultravnc_client.rb
titleUltraVNC 1.0.1 Client Buffer Overflow

Nessus

NASL familyWeb Servers
NASL idWWW_TOO_LONG_URL.NASL
descriptionThe remote web server crashes when it receives a too long URL. It might be possible to make it execute arbitrary code through this flaw.
last seen2020-06-01
modified2020-06-02
plugin id10320
published1999-06-22
reporterThis script is Copyright (C) 1999-2018 Tenable Network Security, Inc.
sourcehttps://www.tenable.com/plugins/nessus/10320
titleWeb Server Long URL Handling Remote Overflow DoS
code
#
# (C) Tenable Network Security, Inc.
#

# Some vulnerable servers:
# SmallHTTP (All versions vulnerable: 2.x Stables, 3.x Latest beta 8)
# OmniHTTPd v2.09 of Omnicron (www.omnicron.ca)
# MyWebServer 1.02
# atphttpd-0.4b ?
# IBM Tivoli Management Framework < Currently Fixpack 2 or Patches 3.7.1-TMF-0066
#   LCFD process - default port 9495)
# IBM Tivoli Management Framework 3.6.x through 3.7.1 (fixed in 4.1)
#   Spider process - default port 94 redirected to another port.
# Lucent Access Point IP Services Router (Formerly known as Xedia Router)
# Oracle9iAS Web Cache/2.0.0.1.0
# TelCondex SimpleWebServer 2.06.20817 Build 3128
# WebServer 4 Everyone
# WebServer 4 Everyone v1.28 (if Host field is set)
# Savant Web Server 3.1 and previous
# WN Server 1.18.2 through 2.0.0 (upgrade to 2.4.4)
# Multitech RouteFinder 550 VPN  (upgrade to RF550VPN_V463)
# Web Server 4D/eCommerce 3.5.3
# ZBServer Pro 1.50-r13
# BRS WebWeaver 1.03
# U.S. Robotics Broadband-Router 8000A/8000-2 (USR848000A-02) running firmware version 2.5
# Polycomm ViaVideo Web component 2.2 & 3.0
# GazTek HTTP Daemon v1.4-3
# WebFS 1.20
# UltraVNC <= 1.0.1
#
########################
# References:
########################
#
# Date: Sat, 12 Oct 2002 07:49:52 +0200
# From:"Marc Ruef" <[email protected]>
# To:[email protected]
# Subject: Long URL crashes My Web Server 1.0.2
#
# Date: Sun, 13 Oct 2002 15:00:18 +0200
# From:"Marc Ruef" <[email protected]>
# To:[email protected]
# Subject: Long URL causes TelCondex SimpleWebServer to crash
#
# Date: Mon, 14 Oct 2002 08:27:54 +1300 (NZDT)
# From:[email protected]
# To:[email protected]
# Subject: Security vulnerabilities in Polycom ViaVideo Web component
#
# From:"David Endler" <[email protected]>
# To:[email protected]
# Date: Tue, 15 Oct 2002 13:12:35 -0400
# Subject: iDEFENSE Security Advisory 10.15.02: DoS and Directory Traversal Vulnerabilities in WebServer 4 Everyone
#
# Delivered-To: mailing list [email protected]
# Date: Tue, 10 Sep 2002 15:39:02 -0700
# Message-ID: <[email protected]>
# From: "Foundstone Labs" <[email protected]>
# To: "announce" <[email protected]>
# Subject: Foundstone Labs Advisory - Buffer Overflow in Savant Web Server
#
# From:"David Endler" <[email protected]>
# To: [email protected]
# Date: Mon, 30 Sep 2002 10:09:59 -0400
# Subject: iDEFENSE Security Advisory 09.30.2002: Buffer Overflow in WN Server
#
# From: "Tamer Sahin" <[email protected]>
# To: [email protected]
# Subject: Web Server 4D/eCommerce 3.5.3 DoS Vulnerability
# Date: Tue, 15 Jan 2002 00:35:59 +0200
# Affiliation: http://www.securityoffice.net
#
# From: "Tamer Sahin" <[email protected]>
# To: [email protected]
# Subject: ZBServer Pro DoS Vulnerability
# Date: Tue, 15 Jan 2002 04:44:37 +0200
# Affiliation: http://www.securityoffice.net
#
# Date:	 Mon, 14 Oct 2002 08:27:54 +1300 (NZDT)
# From:	[email protected]
# To:	[email protected]
# Subject: Security vulnerabilities in Polycom ViaVideo Web component
#
# Date: Sat, 12 Oct 2002 17:02:31 -0700
# To: [email protected]
# Subject: Pyramid Research Project - ghttpd security advisorie
# From: [email protected]
#
# Date: Tue Apr 04 2006 - 14:24:13 CDT
# To: [email protected]
# Subject: Buffer-overflow in Ultr@VNC 1.0.1 viewer and server
# From: Luigi Auriemma (aluigiautistici.org)
#
########################

include("compat.inc");

if (description)
{
 script_id(10320);
 script_version("1.75");
 script_cvs_date("Date: 2018/08/07 16:46:51");

 script_cve_id(
  "CVE-2000-0002",
  "CVE-2000-0065",
  "CVE-2000-0571",
  "CVE-2000-0641",
  "CVE-2001-0820",
  "CVE-2001-0836",
  "CVE-2001-1250",
  "CVE-2002-0123",
  "CVE-2002-1003",
  "CVE-2002-1011",
  "CVE-2002-1012",
  "CVE-2002-1120",
  "CVE-2002-1166",
  "CVE-2002-1212",
  "CVE-2002-1905",
  "CVE-2002-2149",
  "CVE-2003-0125",
  "CVE-2003-0833",
  "CVE-2004-2299",
  "CVE-2005-1173",
  "CVE-2006-1652"
 );
 script_bugtraq_id(
  889,
  1423,
  2979,
  6994,
  7067,
  7280,
  8726,
  17378
 );

 script_name(english:"Web Server Long URL Handling Remote Overflow DoS");
 script_summary(english:"Web server buffer overflow");

 script_set_attribute(attribute:"synopsis", value:
"The remote web server may be affected by a buffer overflow
vulnerability.");
 script_set_attribute(attribute:"description", value:
"The remote web server crashes when it receives a too long URL. It
might be possible to make it execute arbitrary code through this flaw.");
 script_set_attribute(attribute:"solution", value:"Contact the web server's author / vendor for a patch.");
  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:F/RL:OF/RC:C");
  script_set_attribute(attribute:"exploitability_ease", value:"Exploits are available");
  script_set_attribute(attribute:"exploit_available", value:"true");
  script_set_attribute(attribute:"metasploit_name", value:'UltraVNC 1.0.1 Client Buffer Overflow');
  script_set_attribute(attribute:"exploit_framework_metasploit", value:"true");
 script_set_attribute(attribute:"exploit_framework_canvas", value:"true");
 script_set_attribute(attribute:"canvas_package", value:'CANVAS');

 script_set_attribute(attribute:"plugin_publication_date", value:"1999/06/22");

 script_set_attribute(attribute:"potential_vulnerability", value:"true");
 script_set_attribute(attribute:"plugin_type", value:"remote");
 script_end_attributes();

 script_category(ACT_DENIAL);
# All the www_too_long_*.nasl scripts were first declared as
# ACT_DESTRUCTIVE_ATTACK, but many web servers are vulnerable to them:
# The web server might be killed by those generic tests before Nessus
# has a chance to perform known attacks for which a patch exists
# As ACT_DENIAL are performed one at a time (not in parallel), this reduces
# the risk of false positives.

 script_copyright(english:"This script is Copyright (C) 1999-2018 Tenable Network Security, Inc.");
 script_family(english:"Web Servers");

 script_dependencie('http_version.nasl', 'www_multiple_get.nasl');
 script_require_keys("Settings/ParanoidReport");
 script_require_ports("Services/www",80);

 exit(0);
}

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

if (report_paranoia < 2) audit(AUDIT_PARANOID);

port = get_http_port(default:80, embedded:1);

if (http_is_dead(port:port))exit(1, "The web server on port "+port+" is dead");

# Try to avoid FP on CISCO 7940 phone
max = get_kb_item('www/multiple_get/'+port);
if (max)
{
 imax = max * 2 / 3;
 if (imax < 1)
  imax = 1;
 else if (imax > 5)
  imax = 5;
}
else
 imax = 5;
debug_print('imax=',imax,'\n');

# vWebServer and Small HTTP are vulnerable *if* the URL is requested
# a couple of times. Ref: VULN-DEV & BUGTRAQ (2001-09-29)
for (i = 0; i < imax; i = i + 1)
{
 r = http_send_recv3(port: port, method: 'GET', item: strcat('/', crap(65535)));
}


if(http_is_dead(port: port, retry:3))
{
	security_hole(port);
	set_kb_item(name:"www/too_long_url_crash", value:TRUE);
}

Packetstorm

data sourcehttps://packetstormsecurity.com/files/download/83231/ultravnc_client.rb.txt
idPACKETSTORM:83231
last seen2016-12-05
published2009-11-26
reporterMC
sourcehttps://packetstormsecurity.com/files/83231/UltraVNC-1.0.1-Client-Buffer-Overflow.html
titleUltraVNC 1.0.1 Client Buffer Overflow

References