Using Cookies For Selective DoS and State Detection: “

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This is a continuation of he first post where we described how you can use cookies to DoS certain portions of the website. After our speech one of the Mozilla guys came up to us and described another attack that arises from this. Let’s say when a user logs in it sets a cookie that is 200 bytes long, and when they log out it re-sets the same cookie to 50 bytes. Well if the attacker can set a cookie with a particular path to a single image on the site, for instance, they can use JavaScript to check with an onerror event handler to see if the image has loaded.

By combining the over-long cookie (minus 50 bytes) a logged in state will cause the image to fail to load, where as a logged out state will allow the image to load just fine. In this way an attacker can tell cookie states as long as the cookies are variable width and there aren’t other cookies muddying the waters. Interesting attack, I thought!

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(Via ha.ckers.org web application security lab.)

1. Cross site scripting (XSS)

The problem: The “most prevalent and pernicious” Web application security vulnerability, XSS flaws happen when an application sends user data to a Web browser without first validating or encoding the content. This lets hackers execute malicious scripts in a browser, letting them hijack user sessions, deface Web sites, insert hostile content and conduct phishing and malware attacks.

Attacks are usually executed with JavaScript, letting hackers manipulate any aspect of a page. In a worst-case scenario, a hacker could steal information and impersonate a user on a bank’s Web site, according to Snyder.

Real-world example: PayPal was targeted last year when attackers redirected PayPal visitors to a page warning users their accounts had been compromised. Victims were redirected to a phishing site and prompted to enter PayPal login information, Social Security numbers and credit card details. PayPal said it closed the vulnerability in June 2006.

How to protect users: Use a whitelist to validate all incoming data, which rejects any data that’s not specified on the whitelist as being good. This approach is the opposite of blacklisting, which rejects only inputs known to be bad. Additionally, use appropriate encoding of all output data. “Validation allows the detection of attacks, and encoding prevents any successful script injection from running in the browser,” OWASP says.

2. Injection flaws

The problem: When user-supplied data is sent to interpreters as part of a command or query, hackers trick the interpreter — which interprets text-based commands — into executing unintended commands. “Injection flaws allow attackers to create, read, update, or delete any arbitrary data available to the application,” OWASP writes. “In the worst-case scenario, these flaws allow an attacker to completely compromise the application and the underlying systems, even bypassing deeply nested firewalled environments.”

Real-world example: Russian hackers broke into a Rhode Island government Web site to steal credit card data in January 2006. Hackers claimed the SQL injection attack stole 53,000 credit card numbers, while the hosting service provider claims it was only 4,113.

How to protect users: Avoid using interpreters if possible. “If you must invoke an interpreter, the key method to avoid injections is the use of safe APIs, such as strongly typed parameterized queries and object relational mapping libraries,” OWASP writes.

3. Malicious file execution

The problem: Hackers can perform remote code execution, remote installation of rootkits, or completely compromise a system. Any type of Web application is vulnerable if it accepts filenames or files from users. The vulnerability may be most common with PHP, a widely used scripting language for Web development.

Real-world example: A teenage programmer discovered in 2002 that Guess.com was vulnerable to attacks that could steal more than 200,000 customer records from the Guess database, including names, credit card numbers and expiration dates. Guess agreed to upgrade its information security the next year after being investigated by the Federal Trade Commission.

How to protect users: Don’t use input supplied by users in any filename for server-based resources, such as images and script inclusions. Set firewall rules to prevent new connections to external Web sites and internal systems.

4. Insecure direct object reference

The problem: Attackers manipulate direct object references to gain unauthorized access to other objects. It happens when URLs or form parameters contain references to objects such as files, directories, database records or keys.

Banking Web sites commonly use a customer account number as the primary key, and may expose account numbers in the Web interface.

“References to database keys are frequently exposed,” OWASP writes. “An attacker can attack these parameters simply by guessing or searching for another valid key. Often, these are sequential in nature.”

Real-world example: An Australian Taxation Office site was hacked in 2000 by a user who changed a tax ID present in a URL to access details on 17,000 companies. The hacker e-mailed the 17,000 businesses to notify them of the security breach.

How to protect users: Use an index, indirect reference map or another indirect method to avoid exposure of direct object references. If you can’t avoid direct references, authorize Web site visitors before using them

5. Cross site request forgery

The problem: “Simple and devastating,” this attack takes control of victim’s browser when it is logged onto a Web site, and sends malicious requests to the Web application. Web sites are extremely vulnerable, partly because they tend to authorize requests based on session cookies or “remember me” functionality. Banks are potential targets.

“Ninety-nine percent of the applications on the Internet are susceptible to cross site request forgery,” Williams says. “Has there been an actual exploit where someone’s lost money? Probably the banks don’t even know. To the bank, all it looks like is a legitimate transaction from a logged-in user.”

Real-world example: A hacker known as Samy gained more than a million “friends” on MySpace.com with a worm in late 2005, automatically including the message “Samy is my hero” in thousands of MySpace pages. The attack itself may not have been that harmful, but it was said to demonstrate the power of combining cross site scripting with cross site request forgery. Another example that came to light one year ago exposed a Google vulnerability allowing outside sites to change a Google user’s language preferences.

How to protect users: Don’t rely on credentials or tokens automatically submitted by browsers. “The only solution is to use a custom token that the browser will not ‘remember,’” OWASP writes.

6. Information leakage and improper error handling

The problem: Error messages that applications generate and display to users are useful to hackers when they violate privacy or unintentionally leak information about the program’s configuration and internal workings.

“Web applications will often leak information about their internal state through detailed or debug error messages. Often, this information can be leveraged to launch or even automate more powerful attacks,” OWASP says.

Real-world example: Information leakage goes well beyond error handling, applying also to breaches occurring when confidential data is left in plain sight. The ChoicePoint debacle in early 2005 thus falls somewhere in this category. The records of 163,000 consumers were compromised after criminals pretending to be legitimate ChoicePoint customers sought details about individuals listed in the company’s database of personal information. ChoicePoint subsequently limited its sales of information products containing sensitive data.

How to protect users: Use a testing tool such as OWASP’S WebScarab Project to see what errors your application generates. “Applications that have not been tested in this way will almost certainly generate unexpected error output,” OWASP writes.

7. Broken authentication and session management

The problem: User and administrative accounts can be hijacked when applications fail to protect credentials and session tokens from beginning to end. Watch out for privacy violations and the undermining of authorization and accountability controls.

“Flaws in the main authentication mechanism are not uncommon, but weaknesses are more often introduced through ancillary authentication functions such as logout, password management, timeout, remember me, secret question and account update,” OWASP writes.

Real-world example: Microsoft had to eliminate a vulnerability in Hotmail that could have let malicious JavaScript programmers steal user passwords in 2002. Revealed by a networking products reseller, the flaw was vulnerable to e-mails containing Trojans that altered the Hotmail user interface, forcing users to repeatedly reenter their passwords and unwittingly send them to hackers.

How to protect users: Communication and credential storage has to be secure. The SSL protocol for transmitting private documents should be the only option for authenticated parts of the application, and credentials should be stored in hashed or encrypted form.

Another tip: get rid of custom cookies used for authentication or session management.

8. Insecure cryptographic storage

The problem: Many Web developers fail to encrypt sensitive data in storage, even though cryptography is a key part of most Web applications. Even when encryption is present, it’s often poorly designed, using inappropriate ciphers.

“These flaws can lead to disclosure of sensitive data and compliance violations,” OWASP writes.

Real-world example: The TJX data breach that exposed 45.7 million credit and debit card numbers. A Canadian government investigation faulted TJX for failing to upgrade its data encryption system before it was targeted by electronic eavesdropping starting in July 2005.
How to protect users: Don’t invent your own cryptographic algorithms. “Only use approved public algorithms such as AES, RSA public key cryptography, and SHA-256 or better for hashing,” OWASP advises.

Furthermore, generate keys offline, and never transmit private keys over insecure channels.

9. Insecure communications

The problem: Similar to No. 8, this is a failure to encrypt network traffic when it’s necessary to protect sensitive communications. Attackers can access unprotected conversations, including transmissions of credentials and sensitive information. For this reason, PCI standards require encryption of credit card information transmitted over the Internet.

Real-world example: TJX again. Investigators believe hackers used a telescope-shaped antenna and laptop computer to steal data exchanged wirelessly between portable price-checking devices, cash registers and store computers, the Wall Street Journal reported.

“The $17.4-billion retailer’s wireless network had less security than many people have on their home networks,” the Journal wrote. TJX was using the WEP encoding system, rather than the more robust WPA.

How to protect users: Use SSL on any authenticated connection or during the transmission of sensitive data, such as user credentials, credit card details, health records and other private information. SSL or a similar encryption protocol should also be applied to client, partner, staff and administrative access to online systems. Use transport layer security or protocol level encryption to protect communications between parts of your infrastructure, such as Web servers and database systems.

10. Failure to restrict URL access

The problem: Some Web pages are supposed to be restricted to a small subset of privileged users, such as administrators. Yet often there’s no real protection of these pages, and hackers can find the URLs by making educated guesses. Say a URL refers to an ID number such as “123456.” A hacker might say ‘I wonder what’s in 123457?’ Williams says.

The attacks targeting this vulnerability are called forced browsing, “which encompasses guessing links and brute force techniques to find unprotected pages,” OWASP says.

Real-world example: A hole on the Macworld Conference & Expo Web site this year let users get “Platinum” passes worth nearly $1,700 and special access to a Steve Jobs keynote speech, all for free. The flaw was code that evaluated privileges on the client but not on the server, letting people grab free passes via JavaScript on the browser, rather than the server.

How to protect users: Don’t assume users will be unaware of hidden URLs. All URLs and business functions should be protected by an effective access control mechanism that verifies the user’s role and privileges. “Make sure this is done … every step of the way, not just once towards the beginning of any multi-step process,’ OWASP advises.

Quick Help on Windows Dos Commands .

Accessibility Controls = access.cpl
Add Hardware Wizard = hdwwiz.cpl
Add/Remove Programs = appwiz.cpl
Administrative Tools = control admintools
Automatic Updates = wuaucpl.cpl
Bluetooth Transfer Wizard = fsquirt
Calculator = calc
Certificate Manager = certmgr.msc
Character Map = charmap
Check Disk Utility = chkdsk
Clipboard Viewer = clipbrd
Command Prompt = cmd
Component Services = dcomcnfg
Computer Management = compmgmt.msc
Date and Time Properties = timedate.cpl
DDE Shares = ddeshare
Device Manager = devmgmt.msc
Direct X Control Panel (If Installed)* = directx.cpl
Direct X Troubleshooter = dxdiag
Disk Cleanup Utility = cleanmgr
Disk Defragment = dfrg.msc
Disk Management = diskmgmt.msc
Disk Partition Manager = diskpart
Display Properties = control desktop/desk.cpl
Dr. Watson System Troubleshooting Utility = drwtsn32
Driver Verifier Utility = verifier
Event Viewer = eventvwr.msc
File Signature Verification Tool = sigverif
Findfast = findfast.cpl
Folders Properties = control folders
Fonts = control fonts
Fonts Folder = fonts
Free Cell Card Game = freecell
Game Controllers = joy.cpl
Group Policy Editor (XP Prof) = gpedit.msc
Hearts Card Game = mshearts
Iexpress Wizard = iexpress
Indexing Service = ciadv.msc
Internet Properties = inetcpl.cpl
IP Configuration = ipconfig
Java Control Panel (If Installed) = jpicpl32.cpl
Java Application Cache Viewer (If Installed) = javaws
Keyboard Properties = control keyboard
Local Security Settings = secpol.msc
Local Users and Groups = lusrmgr.msc
Logs You Out Of Windows = logoff
Microsoft Chat = winchat
Minesweeper Game = winmine
Mouse Properties = control mouse
Mouse Properties = main.cpl
Network Connections = control netconnections
Network Connections = ncpa.cpl
Network Setup Wizard = netsetup.cpl
Notepad = notepad
Nview Desktop Manager (If Installed) = nvtuicpl.cpl
Object Packager = packager
ODBC Data Source Administrator = odbccp32.cpl
On Screen Keyboard = osk
Opens AC3 Filter (If Installed) = ac3filter.cpl
Password Properties = password.cpl
Performance Monitor = perfmon.msc
Performance Monitor = perfmon
Phone and Modem Options = telephon.cpl
Power Configuration = powercfg.cpl
Printers and Faxes = control printers
Printers Folder = printers
Private Character Editor = eudcedit
Quicktime (If Installed) = QuickTime.cpl
Regional Settings = intl.cpl
Registry Editor = regedit
Registry Editor = regedit32
Remote Desktop = mstsc
Removable Storage = ntmsmgr.msc
Removable Storage Operator Requests = ntmsoprq.msc
Resultant Set of Policy (XP Prof) = rsop.msc
Scanners and Cameras = sticpl.cpl
Scheduled Tasks = control schedtasks
Security Center = wscui.cpl
Services = services.msc
Shared Folders = fsmgmt.msc
Shuts Down Windows = shutdown
Sounds and Audio = mmsys.cpl
Spider Solitare Card Game = spider
SQL Client Configuration = cliconfg
System Configuration Editor = sysedit
System Configuration Utility = msconfig
System File Checker Utility = sfc
System Properties = sysdm.cpl
Task Manager = taskmgr
Telnet Client = telnet
User Account Management = nusrmgr.cpl
Utility Manager = utilman
Windows Firewall = firewall.cpl
Windows Magnifier = magnify
Windows Management Infrastructure = wmimgmt.msc
Windows System Security Tool = syskey
Windows Update Launches = wupdmgr
Windows XP Tour Wizard = tourstart
Wordpad = write

Hope someone finds it somewhat usefull!?!

What is Net Tools :

Net Tools is a comprehensive set of host monitoring, network scanning, security, administration tools and much more, all with a highly intuitive user interface. It’s an ideal tool for those who work in the network security, administration, training, internet forensics or law enforcement internet crimes fields. Net Tools is mainly written in Microsoft Visual Basic 6, Visual C++, Visual C# and Visual Studio .NET.

Screenshots

Here are a few screenshots of Net Tools 5. Click to enlarge.

Download Net Tools 5.0

[ download ] (version 5.0.70)

Features:

Net Tools 5.0 (build 70) contains a whole variety of network tools. Here is a list of the most important tools:

1) IP Address Scanner
2) IP Calculator
3) IP Converter
4) Port Listener
5) Port Scanner
6) Ping
7) NetStat (2 ways)
8 ) Trace Route (2 ways)
9) TCP/IP Configuration
10) Online – Offline Checker
11) Resolve Host & IP
12) Time Sync
13) Whois & MX Lookup
14) Connect0r
15) Connection Analysator and protector
16) Net Sender
17) E-mail seeker
18) Net Pager
19) Active and Passive port scanner
20) Spoofer
21) Hack Trapper
22) HTTP flooder (DoS)
23) Mass Website Visiter
24) Advanced Port Scanner
25) Trojan Hunter (Multi IP)
26) Port Connecter Tool
27) Advanced Spoofer
28) Advanced Anonymous E-mailer
29) Simple Anonymous E-mailer
30) Anonymous E-mailer with Attachment Support
31) Mass E-mailer
32) E-mail Bomber
33) E-mail Spoofer
34) Simple Port Scanner (fast)
35) Advanced Netstat Monitoring
36) X Pinger
37) Web Page Scanner
38) Fast Port Scanner
39) Deep Port Scanner
40) Fastest Host Scanner (UDP)
41) Get Header
42) Open Port Scanner
43) Multi Port Scanner
44) HTTP scanner (Open port 80 subnet scanner)
45) Multi Ping for Cisco Routers
46) TCP Packet Sniffer
47) UDP flooder
48) Resolve and Ping
49) Multi IP ping
50) File Dependency Sniffer
51) EXE-joiner (bind 2 files)
52) Encrypter
53) Advanced Encryption
54) File Difference Engine
55) File Comparasion
56) Mass File Renamer
57) Add Bytes to EXE
58) Variable Encryption
59) Simple File Encryption
60) ASCII to Binary (and Binary to ASCII)
61) Enigma
62) Password Unmasker
63) Credit Card Number Validate and Generate
64) Create Local HTTP Server
65) eXtreme UDP Flooder
66) Web Server Scanner
67) Force Reboot
68) Webpage Info Seeker
69) Bouncer
70) Advanced Packet Sniffer
71) IRC server creater
72) Connection Tester
73) Fake Mail Sender
74) Bandwidth Monitor
75) Remote Desktop Protocol Scanner
76) MX Query
77) Messenger Packet Sniffer
78) API Spy
79) DHCP Restart
80) File Merger
81) E-mail Extractor (crawler / harvester bot)
82) Open FTP Scanner
83) Advanced System Locker
84) Advanced System Information
85) CPU Monitor
86) Windows Startup Manager
87) Process Checker
88) IP String Collecter
89) Mass Auto-Emailer (Database mailer; Spammer)
90) Central Server (Base Server; Echo Server; Time Server; Telnet Server; HTTP Server; FTP Server)
91) Fishing Port Scanner (with named ports)
92) Mouse Record / Play Automation (Macro Tool)
93) Internet / LAN Messenger Chat (Server + Client)
94) Timer Shutdown/Restart/Log Off/Hibernate/Suspend/ Control
95) Hash MD5 Checker
96) Port Connect – Listen tool
97) Internet MAC Address Scanner (Multiple IP)
98) Connection Manager / Monitor
99) Direct Peer Connecter (Send/Receive files + chat)
100) Force Application Termination (against Viruses and Spyware)
101) Easy and Fast Screenshot Maker (also Web Hex Color Picker)
102) COM Detect and Test
103) Create Virtual Drives
104) URL Encoder
105) WEP/WPA Key Generator
106) Sniffer.NET
107) File Shredder
108) Local Access Enumerater
109) Steganographer (Art of hiding secret data in pictures)
110) Subnet Calculater
111) Domain to IP (DNS)
112) Get SNMP Variables
113) Internet Explorer Password Revealer
114) Advanced Multi Port Scanner
115) Port Identification List (+port scanner)
116) Get Quick Net Info
117) Get Remote MAC Address
118) Share Add
119) Net Wanderer
120) WhoIs Console
121) Cookies Analyser
122) Hide Secret Data In Files
123) Packet Generator
124) Secure File Splitting
125) My File Protection (Password Protect Files, File Injections)
126) Dynamic Switch Port Mapper
127) Internet Logger (Log URL)
128) Get Whois Servers
129) File Split&Merge
130) Hide Drive
131) Extract E-mails from Documents
132) Net Tools Mini (Client/Server, Scan, ICMP, Net Statistics, Interactive, Raw Packets, DNS, Whois, ARP, Computer’s IP, Wake On LAN)
133) Hook Spy
134) Software Uninstaller
135) Tweak & Clean XP
136) Steganographic Random Byte Encryption
137) NetTools Notepad (encrypt your sensitive data)
138) File Encrypter/Decrypter
139) Quick Proxy Server
140) Connection Redirector (HTTP, IRC, … All protocols supported)
141) Local E-mail Extractor
142) Recursive E-mail Extractor
143) Outlook Express E-mail Extractor
144) Telnet Client
145) Fast Ip Catcher
146) Monitor Host IP
147) FreeMAC (MAC Address Editor)
148) QuickFTP Server (+user accounts support)
149) NetTools Macro Recorder/Player (Keybord and Mouse Hook)
150) Network Protocol Analyzer
151) Steganographic Tools (Picture, Sounds, ZIP Compression and Misc Methods)
152) WebMirror (Website Ripper)
153) GeoLocate IP
154) Google PageRank Calculator
155) Google Link Crawler (Web Result Grabber)
156) Network Adapter Binder
157) Remote LAN PC Lister
158) Fast Sinusoidal Encryption
159) Software Scanner
160) Fast FTP Client
161) Network Traffic Analysis
162) Network Traffic Visualiser
163) Internet Protocol Scanner
164) Net Meter (Bandwidth Traffic Meter)
165) Net Configuration Switcher
166) Advanced System Hardware Info
167) Live System Information
168) Network Profiler
169) Network Browser
170) Quick Website Maker and Web Gallery Creator
171) Remote PC Shutdown
172) Serial Port Terminal
173) Standard Encryptor
174) Tray Minimizer
175) Extra Tools (nmap console & win32 version)

Many extra features and utilities are included in this package!

Download Net Tools 5.0

[ download ] (version 5.0.70)