One thing I notice is the large numbers of people who keep making the same require() or include() mistakes in php which allow attackers to run remote code. If you look at the relevant full disclosure lists there are several of these posted every week - Scanning tools like the Qualys Scanner spend a large amount of time looking for these easily preventable bugs - there must be thousands of these.

Make open source more secure, share your experience, police each other, make M$ security look bad. When you make a security fix in code make sure you comment it - someone is probably going to copy it as an example. Don't let mistakes or inexperience spread.

1. Unvalidated Parameters
2. Broken access control
3. Broken account and access management
4. Cross-site scripting (XSS) flaws
5. Buffer overflows
6. Command injection flaws
7. Error Handling problems
8. Insecure use of cryptography
9. Remote administration flaws
10. Web and application misconfiguration

"I like my web servers just like my women...insecure and full of holes waiting to be exploited." --Bill G.

Come on, Microsoft has listed these problems for years now... in the form of Service packs and hot fix descriptions... Sure it wasn't in a bullet form list... but each description had at least one thing from the list...

The real problem is lack of time to properly test code. Somehow in modern businesses, very little time is allocated to GOOD, extensive, useful testing for vulnerablities in apps.

It's a nice start and definately points out some things developers should be aware of. But how about someone puts together a more specific checklist/tutorial for each point and write it around their favorite development language (PHP, ASP (cough), etc.). Who's not busy?

Misconfigured Users

..to those who didnt bother to read the article, it has these lines in it:

This security document is not about firewalls, encryption and patching. It's about common, highly exploitable errors made by the application programmers.

which means every post thats about IIS, Micro$oft, m$, microshaft and god knows what other words you use to make you look like an idiotic open source fanatic with no sense of reality are offtopic.

The Open Web Application Security Project (OWASP) is dedicated to helping organizations understand and improve the security of their web applications and web services. This list was created to focus government and industry on the most serious of these vulnerabilities. Web application security vulnerabilities are highly exploitable and the consequence of an attack can be devastating. These vulnerabilities represent an equivalent magnitude of risk as network security problems, and should be given the same degree of attention.

Using this list, organizations can send a message to web site developers that "we want you to make sure that you won't make these mistakes." The security issues raised here are not new. In fact, some have been well understood for decades. Yet for some reason, major software development projects are still making these mistakes and jeopardizing not only their customers' security, but also the security of the entire Internet. You can download the entire report in PDF format here

Top Vulnerabilities in Web Applications

A1
Unvalidated Parameters
Information from web requests is not validated before being used by a web application. Attackers can use these flaws to attack backside components through a web application.

A2
Broken Access Control
Restrictions on what authenticated users are allowed to do are not properly enforced. Attackers can exploit these flaws to access other users' accounts, view sensitive files, or use unauthorized functions.

A3
Broken Account and Session Management
Account credentials and session tokens are not properly protected. Attackers that can compromise passwords, keys, session cookies, or other tokens can defeat authentication restrictions and assume other users' identities.

A4
Cross-Site Scripting (XSS) Flaws
The web application can be used as a mechanism to transport an attack to an end user's browser. A successful attack can disclose the end user's session token, attack the local machine, or spoof content to fool the user.

A5
Buffer Overflows
Web application components in some languages that do not properly validate input can be crashed and, in some cases, used to take control of a process. These components can include CGI, libraries, drivers, and web application server components.

A6
Command Injection Flaws
Web applications pass parameters when they access external systems or the local operating system. If an attacker can embed malicious commands in these parameters, the external system may execute those commands on behalf of the web application.

A7
Error Handling Problems
Error conditions that occur during normal operation are not handled properly. If an attacker can cause errors to occur that the web application does not handle, they can gain detailed system information, deny service, cause security mechanisms to fail, or crash the server.

A8
Insecure Use of Cryptography
Web applications frequently use cryptographic functions to protect information and credentials. These functions and the code to integrate them have proven difficult to code properly, frequently resulting in weak protection.

A9
Remote Administration Flaws
Many web applications allow administrators to access the site using a web interface. If these administrative functions are not very carefully protected, an attacker can gain full access to all aspects of a site.

A10
Web and Application Server Misconfiguration
Having a strong server configuration standard is critical to a secure web application. These servers have many configuration options that affect security and are not secure out of the box.

Press Release
Washington, D.C. -- A new report detailing the ten most critical web application security problems was unveiled today by the Open Web Application Security Project. OWASP is dedicated to helping organizations understand and improve the security of their web applications and web services. Download the report from the OWASP website at http://www.owasp.org.

"The OWASP Top Ten list shines a spotlight directly on one of the most serious and often overlooked risks facing government and commercial organizations," said Jeffrey Williams, CEO of web application security firm Aspect Security. "A stunning number of organizations spend big bucks securing the network and somehow forget about the applications."

These flaws are surprisingly common and can be exploited by unsophisticated attackers with easily available tools. When an organization deploys a web application, they invite the world to send HTTP requests. Attacks buried in these requests sail past firewalls, filters, platform hardening, SSL, and IDS without notice because they are inside legal HTTP requests. Therefore, web application code is part of the security perimeter and cannot be ignored.

"This list is an important development for consumers and vendors alike," said Stephen Christey, Mitre CVE editor. "It will educate vendors to avoid the same mistakes that have been repeated countless times in other web applications. But it also gives consumers a way of asking vendors to follow a minimum set of expectations for web application security and, just as importantly, to identify which vendors are not living up to those expectations"

"This 'Ten-Most-Wanting' List acutely scratches at the tip of an enormous iceberg," said Peter G. Neumann, moderator of the ACM Risks Forum. "The underlying reality is shameful: most system and Web application software is written oblivious to security principles, software engineering, operational implications, and indeed common sense."

The Open Web Application Security Project (OWASP) is an Open Source community project staffed entirely by volunteer experts from across the world. Project chair Mark Curphey said, "the OWASP Top Ten Project was formed to capture our collective wisdom and present it in a way that would bring the attention web application security deserves."

Questions or comments about the OWASP Top Ten should be sent to: topten@owasp.org

So, you're telling me that I *shouldn't* write web apps with remote exploits, buffer overflows and generally crappy security?!?!? Well color me flabbergasted!

Top 10 Vulnerabilities in Web Applications

This seems to be a moving target, though with the first vendor or platform that jumps to mind regarding vulnerabilities is a given. I'd say the root class is MicrosoftVulnerability and subclasses are Windows, Explorer, Outlook, Office, etc, all of which should be behind a firewall and virus/worm filters. Exposing an MS workstation to the internet is asking for it. However...

On unixes (including BSD and Linux) there's been the danger of unexpected post commands on webservers, directory access, etc. When I coded a perl search engine, years ago I found I had to absolutely lock down what was accepted as parameters and subsequent values. Frequenly processes ran with root authority, to access all resources. Granted this was probably the fault of the admin, not wanting to devote time and effort to make all necessary resources available to a special account for scripts to run in. Does this hold true today? (Obviously directories are still frequently available, even on CNN :o)

Time for new glasses.

Though I would like to see Buffy overflow every now and then.

Though I think this is useful information, anyone whose been doing web app development for awhile knows these by heart, and by a few other organs as well.

I can't really get worked up over this announcement, what can I say?

A11 Link on Slashdot

In spite of many alarming examples, the danger associated with having a link to your web site posted on the Slashdot front page continues to be underestimated by many developers of web applications. Neglect of this threat can cause your web server to actually burn through the floor of your computer building in a manner similar to nuclear meltdown.

"The underlying reality is shameful: most system and Web application software is written oblivious to security principles, software engineering, operational implications, and indeed common sense."

I think a lack of common sense is a problem which applies to almost everything. Judges, certain chip-manufacturing companies, certain companies preventing sales of their better (*cough*alpha*cough*) products, etc, all seem to suffer from this affliction.

Another facet which the article may have neglected to mention is programmers who feel that they're better than the rest of their fellow programmers and so as a result they 'assume' that their software is inherently bug free, because obviously they could never write a buggy applcation.

In the recent case of HP and the Alpha, it seems as though both conceit ('our new chips are better', while quietly ignoring the facts) and a lack of common sense ('hey, how bout we not sell our better and more lucrative product, cuz thatll be fun!') and a dose of good ol' fashioned stupidity are involved...

Lack of common sense, conceit, and stupidity.. While the specifics of this article are clearly about web design, the overall lessons to be learned can, and should, be applied to technology, and life in general.

It's about time common sense became a bit more deserving of the title, and maybe once that happens we won't have to read articles like this one.

This is far from a "must read", it's good introduction to common mistakes junior developers/admins make with webapps. There's nothing in there that hasn't been covered before or is well-known to anyone who has even the least bit of real-world experience.

It seems like good information and it's well-written, but it's hardly anything ground breaking.

Don't just scan the summary.. There's nothing that special about the top 10. Read the PDF which actually explains each item, giving examples and what to do about it. That is what makes the site worth looking at.

www.cgisecurity.com/lib [cgisecurity.com]

I guess that you can break these down but to me it seems that the top vulnerabilities are:

Crappy Code - Some of the people that are writting applications today either never learned about security or just don't care. This spans both the closed and open source world (there are examples in both).

Bad Configuration - How many times do we hear about Joe (no offense if your name is Joe and you are an admin) admin configure a webserver (or application) and leave some huge wide open hole because they either couldn't understand the directions in the README or never bothered to look. Then they whine about it when they get 0wn3d .

Unfortunately, they forgot:

-Application allows user to upload a file (attachment, image, etc) somewhere into the webroot.
-Instead of sending a .jpg, the application allows the user to upload a file of any name.
-User uploads "mail_me_your_sources.php", or similar
-This upload becomes executable, user has control of server

S

Here's a quick and language independent example of how easy it is to miss a security hole in a web application: Say you've created a message board with the ability to edit posts. When a user clicks the edit button they get a form with a textarea to type in and the messageID as a hidden field. When they submit the form you do something like this in SQL:

UPDATE forum
SET comment = form.comment
WHERE messageID = form.messageID

Do you see the error there? I can edit the form to send a different messageID and change any comment I want. The solution?

WHERE messageID = form.messageID AND userID = cookie.userID

Because HTML is stateless, you have to authenticate the user on every hit and use that authenticated identity as part of every database action. How you do that is a subject unto itself!

At any rate, I just wanted to show how easy it is to introduce a serious security flaw into a web application. The only countermeasure is competent, careful coding.

The article is just a summary. If you want to know more check out: Hacking Web Solutions Exposed [amazon.com]

Read any of the following stories, and they all basically assert the same thing. It usually boils down to the nut holding the keyboard - human error:

• June 2, 2000 - E-Commerce Times - 'Top 10 List' Reveals Internet Security Flaws" [ecommercetimes.com]
• October 21, 2001 - Tech TV - FBI Releases List of Top 20 Computer Risks [techtv.com]
• Monday, September 30, 2002 - PCWorld/Yahoo - List of Top 20 Software Flaws Due [yahoo.com]
• October 17, 2002 - SANS/FBI - The Twenty Most Critical Internet Security Vulnerabilities [sans.org]

Yes, all of these vulnerabilities are well known, but the reason that they are common mistakes is because it is so much easier to make them than to avoid them. Making people aware of them isn't the same as instructing people in how to avoid them.

While the list is (appropriately) in OS-neutral and scripting language-neutral terms, the way to correct these problems is specific to the OS, webserver and scripting langauge you are using. So the next question is: what are the resources for addressing these issues, specifically, for particular OSes, webservers and languages?

For those taking the MS approach (and flame it if you want, but IIS isn't about to stop being the #2 web server overnight, so it might as well be done as securely as possible), I can recommend the following two guides from SANS:

Securing Internet Information Server [sans.org]

and

Windows 2000/XP Scripting For Security [sans.org]

These are listed as "course books" on their site, but they stand alone as guides for those who already have some background and knowledge. And if you don't have much background and knowledge, SANS courses are very good. (In fact, just about everything at the SANS website [sans.org] is valuable for the IT professional who wants to know more about security -- which ought to be all of us.)

So, stop just posting that these 10 problems are old news, and post the resources you use (or learned from) to avoid these problems yourself on your platform of choice, so the many (majority?) still making these mistakes can learn to avoid them too.

...will be spread in JPEGs, GIFs, PDFs, .txt files, etc.

I don't think anyone has spent too much time looking for buffer overflows in the most common decoders for these filetypes; and I'm sure they exist.

As soon as someone figures out how to the Microsoft's LZW decompressor to overrrun its stack, or how to get a stack corruption in Adobe's Acrobat reader, it will be possible to spread viruses easily, becuase most people aren't afraid to open .GIF or .PDF files.

I've read it here many times: "web programming is easy, it's not like real programming". The problem is that managers and decision makers also read this kind of un-informed statement.

The truth is that it is easy to get something going on a website, but it is hard to get something that works well and is secure. The amount of time it takes to transform an interesting web demo to a well executed web application is staggering. It is also very hard to explain why all that time is needed. What happens is that web application get launched half-baked. If a company is lucky, the application will only annoy the users, if a company is unlucky, someone will walk right in through a common security hole and comprimise the whole application.

Moral to managers and project planners: believe your programmers when they tell you that there is more then meets the eye in developing web applications.

- having foo.php.bak files.
if these files access databases or contain other passwords they're likely to be visible in the .bak file.

- .inc files.
same probmen if .inc isn't parsed or blocked in any way.