Wednesday, April 27, 2016

DeepViolet SSL/TLS Scanning Tool Updated

Updated on April 29, 2016

DeepViolet updated to Beta2.  A number of bugs have been fixed and new features added.  The tool can be run from the command line or alternatively as a desktop GUI application.  Refer to the GitHub DeepViolet documentation for more detail.  Following is an overview of the command line options for quick reference.

usage: java -jar dvCMD.jar -serverurl [-wc | -rc ]
            [-h -s{t|h|r|c|i|s|n}]
            Ex: dvCMD.jar -serverurl -sections ts
            Where sections are the following,
            ;t=header section, h=host section, r=http response section,
            c=connection characteristics section, i=ciphersuite section,
            s=server certificate section, n=certificate chain section
   -h,--help Optional, print dvCMD help options.
   -rc,--readcertificate Optional, read PEM encoded certificate
            from disk. Ex: -rc ~/certs/mycert.pem
   -s,--sections Optional, unspecified prints all section
            or specify sections. [t|h|r|c|i|s|n]
   -u,--serverurl Required for all options except
            -readcertificate, HTTPS server URL to
   -wc,--writecertificate Optional, write PEM encoded certificate to
            disk. Ex: -wc ~/certs/mycert.pem

Or alternative use the desktop application.

Photo 1: DeepViolet Desktop Application

Friday, April 22, 2016

Woodsy Owl 2016 - Don't Pollute Software!

It's been 6-years David Rice's presentation and 4-years since my related blog post.  I can safely assume it had some impact on me.  I'm not sure if pollution or health care is the better metaphor for security but clearly national action is needed.  It's interesting to me society could mustered the interest and investment to improve national sentiment around pollution.  Software security is no less of a challenge.  I'm confident such an effort will develop around software security someday.  There's no way society can continue the present course of increasing size and scope of national security incidents while continuing to shrug them off.  Someday the level of pain, suffering, and public outcry will force action.

Tuesday, April 19, 2016

Weaknesses with Short-URLs

Recent research was presented[1] raising security and privacy concerns around URL shortening services like,, and others.  The services are used to shorten lengthy URL's to more compatible URLs suitable for online use.  Smaller URLs also provide ancillary benefit since they are easier to remember.  My first impression was the recent research[1] on URL shorteners was that it was specious since URL shortening was never intended or designed as a security and privacy control from the start.  Reading the research softened my initial opinion.  The seeming randomness of these short URLs provides the public unfounded confidence of their utility for security.  Specifically, the false idea that others will not discover the link since it appears secure - difficult to guess.  Unfortunately, the part of the URI providing the identity for the long URL, is as few a 6-characters for some shortening services, far too small a space to be cryptographically secure, and easily brute forceable by attackers and demonstrated by researchers.

The research paper was not the first cracks in the short URL armor.  The following presents some concerns I gathered across different resources from other researchers.  I also share some personal thoughts about short URL weaknesses that I have not noticed elsewhere.  I don't stake any claim to these and I'm simply passing them along to raise awareness.  I'm betting we have not seen the last around security and privacy concerns with short URLs.

1) Short URLs not secure
As researchers mention[1] these links are not secure and easily brute forced.  This may or may not be a concern for you depending on how you use them.

2) Short URLs target host unknown until clicked
Phishing is a problem for everyone.  Short URLs exacerbate an already bad email phishing problem.  There are some services like where email users can unwind these URLs but most people will never do this.  People are trusting and verification takes extra work.  Clicking a shortened URL is like hitchhiking in a strangers car, you don't know where it's taking you.

3) Obfuscated redirects
Brian Krebs makes an interesting point[3], attackers can leverage an open redirect on a government host and create a short branded URL.  The result is an authentic URL that looks like it navigates to a government web site but instead navigates to the attackers malware site.

This URL

Becomes this branded URL (notice the .gov domain, ouch!)

The combination of an open redirect and short URL branding creates a situation of misplaced trust or false sense of security.  Users think clicking will take them to a government site when if fact it takes them to another site entirely.  The moral of the tale, if you have any open redirects in your web site your in trouble but if you also use branded URL shorteners your setting the public up for malware and phishing attacks.

4) Obfuscate payloads
A spin on Krebs idea I considered is that any arbitrary payload can be saved in a long URL by attackers and hidden from prying eyes - a payload.  For example, on some services it's possible to create arbitrary URLs with invalid hosts and parameters so long as those URLs are syntactically correct.  Meaning if I create a URL some shortening services are not checking to ensure host xyz is a valid host.  Even if the host is valid, URI parameters may be developed that legitimate hosts ignore entirely like the following,,b=c.  Some servers like Blogger ignore superfluous parameters like a=b,b=c in the request if you pass them.  Attackers can create any URL they want.  I used the following in a quick test, (x10,000 zeros, for a 10k URL)

I created a bogus URL with a 10KB URI that consisted of a slash (/) followed by 10,000 zeros and was successful.  Attackers can store payloads in these bogus URLs to use for a variety of purposes.  Outside of validating the syntax and host, shortening services have no idea of knowing if these URIs are valid and, in their defense, there's probably not a good way for them to validate.  Therefore, they must store the entire long URL.  This means an attacker can use URL shortening services, to hide small chunks of arbitrary data for nefarious purposes like command and control for bot networks, torrent information, etc.  URL shortening sites undoubtably provide security intrusion and content controls.  There's likely some limits in size or number of URL per second they will accept, etc.  I'm not sure what they are but it's likely they vary between shortening services.

5) Multiple indirection
Some of the URL shorting services will not accept their own URLs for a long URL but at least a few of them will accept shorted URLs of other services.  Therefore it's possible to create multiple levels of indirection. short URLs referring to other short URLs.  How many levels can be created?  I'm not sure.  It seems like browsers must have some practical level of redirect control but I have no idea.  I'm not sure if this serves a practical purpose yet but at the very least it complicates organizational IT forensics.

6) Infinite loops
I was wondering if I could create two or more short URLs referring to each other.  To get this to working requires an understanding of the shortening algorithm such that the attacker can determine the shortened URI before it's created.  Or perhaps a shortening services that allows changing a long URL after the short URL has been created.  This will allow an attacker to create short URLs that either directly or indirectly refer to each other.  I didn't spend much time looking at this.  I tried to find some code online to see if there were any standard algorithms.  I was thinking everyone may be leveraging an open source project so I could determine the algorithm easily.  Nothing was obvious, I was not successful.  Perhaps someone else may want to take this up.  I'm not sure if the browser is smart enough to detect these types of infinite redirects or not.  If not, it seems plausible it could be used to hang or crash the browser.  Even if possible, I'm not sure this has any practical value for attackers anyway.

7) XSS in URLs
I tried to see if I could get JavaScript inside a long URL and then shorten it to bypass browser security controls.  No success.  I tried using the javascript URI scheme type.  Some URL shorteners allowed it but at least Chrome and Safari were smart enough to handle the redirects as a html scheme type regardless of the scheme type I provided.  I also tried the data scheme type with no positive result.  Data works when pasted directly into the browser URL bar but not successful as a redirect.  Again handled like html scheme type regardless of the specified scheme.  Browsers are a battle hardened environment, good news for us.

8) Shortener Service Unavailability
If the shortening services goes away temporarily or permanently it impacts the services anywhere shortened links are embedded.  What happens to Twitter if goes away?  Not good.  DDOSing is essentially the same as DDOSing Twitter since a better part of Twitters content would be unreachable for users if cannot respond. has a big list of shortening services[2]. also tracks shortening services no longer available and there's many more of them I was aware.  If shortening is part of your business strategy, or your users are using it, you may want to consider all your available options and weight risks, reliable services, hosting your own, etc.

Keep in mind my tests were not comprehensive and exhaustive.  I didn't want to do anything that could be considered offensive.  So if noted a test was successful it may not be successful across all services.  Conversely if a test was unsuccessful if may not be unsuccessful everywhere.  An important consideration, while there are some problems with URL shorteners there's not a good immediate option for avoiding them.  If your going to participate in social media your going to be using short URLs like it or not until improvements are made.

[1] Gone in Six Characters: Short URLs Considered Harmful for Cloud Services
[2] Bit,do list of URL Shorteners
[3] Spammers Abusing Trust in US .Gov Domains

* Landminds image from World Nomads

Friday, April 8, 2016

Funniest Security/Privacy Tweet of 2016

Soghoian is referring to a piece of tape FBI Director Comey places over his laptop camera.  The subtle message for the public is that electronic privacy is for the privileged elite.


Photo: click to enlarge

I see a lot of companies without top security leadership representation, CISO's.  Check out a few company leadership pages sometime.  The point is that with no application security expert in the board room don't expect security concerns to be raised until your next public security incident.  Keep in mind the job of the CISO is not scape goat for your next public security incident; we are way past that now, it's to identify and reduce business risks/injury posed by technology products/services to acceptable levels.  Two points, 1) you need a CISO, 2) hire a knowledgeable CISO if you like your executive job or board position.

A couple of cases that could have been avoided or gone much better with a knowledgeable CISO...  The Matter of LabMD, Inc.  Target CEO Fired - Can You Be Fired If Your Company Is Hacked?

*Photo from Transformers film, 2007

Thursday, April 7, 2016

Vulgar Furry Ramblings

ARS: Nation-wide radio station hack airs hours of vulgar “furry sex” ramblings

The article goes on to conclude, "...advisory suggests that users should change passwords to the Web interface.."  No zero days or exotic hacks, only attackers doing their homework.  There's a strong possibility KIFT could have avoided the entire mess if they changed default factory credentials.

Application Security and Privacy One Year Ago

Some security gems from around April 2015.

Last Week Tonight with John Oliver: Government Surveillance (HBO)

Application Security Meme

Tuesday, April 5, 2016

Fortune Top-100 CISO's Not Well Equipped to Defend Software

Updated on April 16, 2016

To understand why online systems are plagued with seemly endless security incidents requires a closer look into today's security landscape.  Let's look first to understand the vulnerable systems criminals exploit.  Top security company WhiteHat says it best on their home page.
Photo 1: Except home page (click to enlarge)
According to WhiteHat web applications are the greatest risk area.  Next WhiteHat says, "...most security budgets are spent on securing and monitoring the perimeter and endpoints".   According to the FBI 2014 Internet Crime Report, "...IC3 received 269,422 complaints with an adjusted dollar loss of $800,492,073...", keep in mind this is US losses, not global.
"...IC3 received 269,422 complaints with an adjusted dollar loss of $800,492,0731...", FBI 2014 Internet Crime Report
Aside from the claims and statistics, it does not take a security expert to understand the global force behind the online movement.  Virtually every product and service is moving online and it stands to reason the criminals and crime are following the money.

Let's change gears, let's look into background on today's top security executive the, Chief Information Security Officer (CISO).  The following is Digital Guardian[INFOGRAPHIC] infographic for Fortunes 100's top CISO's.

Photo 2: Infographic DigitalGuardian web site
The infographic tells us CISO's are predominately male, well educated, hold various security and audit certifications.  In short, nothing particularly remarkable outside of our expectations but take a look at the following, 59% of CISO's have IT work background with only 13% in programming/engineering experience.
Fortune 100 CISOs are not well equipped with the skills necessary to defend today's vulnerable web applications
Makes sense, for years IT leaders have been successfully defending permitters with firewalls.  In all fairness, firewalls will always be valuable but they have not proven as effective defending online applications as well as IT infrastructure.  Indications are Fortune 100 CISOs are not well equipped with the skills necessary to defend today's vulnerable web applications.  Let's look at some of the reasons why.

Writing software code, software architecture, debugging, understanding the battery of tools, is an entire domain of expertise.  Can programming be learned like any other challenge?  Of course, but let's give programmers some credit, application development is an entire domain of knowledge and takes takes years to master.  Once that domain is mastered, learning to think like an attacker, breaking systems, secure coding techniques, secure coding libraries, dynamic and static analysis security tools are, in all fairness, is an entire new domain of expertise to master and not taught in most universities.  A top defender of software and secure software designer is a unique skill set.  This is why those that break into systems (e.g., pentesters) or secure traditional IT infrastructure don't necessarily make the best application defenders.

Attacks occur where you least expect them and it's often frustrating to newcomers in the application security profession

To give some idea of the learning challenges, learning basic programming principles like writing a "Hello World" program in Java will take about 10 minutes of time.  Learning object oriented design techniques principles, some months.  Learning the various Apache and open source packages you need to be competitive in a business environment can take years.  Understanding how to defend all that technology takes years of working through incidents, developing the security mindset, understanding the tools and techniques.  A strong technical leader requires mastery of two domains, software development and security.  If you wanted a leader for security engineering this is all you would need but you don't, you want a CISO.  Now you need someone who also knows how to frame security challenges to smart executives and board members that may not be very technical.  Strong CISO are rare individuals in high demand.

Photo:  ThreatTrack Security (click enlarge)
Today security is largely a software quality problem that can't be addressed with the next vendor security-in-box-solution.  Software security is a business and engineering quality problem - not an act of God.  Software code must be designed, built, and delivered securely.  Each step in the software development process, inception, architecture, development, testing, deployment, sunsetting, is important in the overall solution quality and historically entirely within the domain of software engineering groups.  Let's face it, software engineering leaders don't necessarily appreciate security advice around how to build systems.  Especially when the suggested security quality improvements reduce execution tempo which is closely related to performance based compensation.

Today security is largely a software quality problem that can't be addressed with the next vendor security-in-box-solution.  Software code must be designed, built, and delivered securely

Significantly reducing business risk depends on the CISO's ability to influence and win the support of software developers, development leaders, business executives, and board members.  Even a CISO with the best background and skills may not be able to influence positive code quality security improvements.  A CISO is not an army of one.  A knowledgeable CISO will fail without the proper support across business constituencies.  This is because security is everyone's job, not only the job of the CISO and their staff.   Influencing systemic positive change throughout an organization is difficult but it begins with role dependent education.  Today's CISO's must be as comfortable reviewing and recommending security architecture to a developer on the whiteboard as explaining business implications of security vulnerability to corporate boards.  CISO's must explain why engineering quality processes must be improved and recommend specific improvements when requested.  CISO's with best blend of technology and business experience have the best chance for improving software code quality and influencing the most positive changes to security and winning respect of developers.

As our most valuable assets are brought online as Internet web applications, criminals abscond with our data while companies are busy tweaking firewalls.  Many companies are squandering security investments prodigiously in the wrong areas.  Indications are Fortune Top-100 CISO's don't have the best blend of skills and experience to defend software systems - the primary weakness.

The trend is that all executives share security responsibility in a significant security incident so the value of a knowledgeable security executive should not be underestimated

The best CISO defenders of tomorrow will be those with experience coding/programming, designing, shipping software products and services.  If a security leader with a development background is not available - build one.  Find a top engineering leader and begin building the security mindset.  Send them to security conferences where executives congregate like, Gartner IT Security Summit.  Understanding business implications of security, executive concerns around security, and how to communicate with executives are essential.  Send them to SANS Institute to learn how to break software applications.  Theory is helpful but hands on skills are essential.  Attend security conferences like Blackhat, DEFCON, and others.  It can take years to find the best leader and build out a team.  Begin now, by investing in your own organization and growing some organic talent.  The trend is that all executives share security responsibility in a significant security incident so the value of a knowledgeable security executive should not be underestimated.

Monday, April 4, 2016

CNBC: Execs We're Not Responsible for Cybersecurity

CNBC: Execs We're Not Responsible for Cybersecurity, "...executives like CEOs and CIOs, and even board members — didn't feel personally responsible for cybersecurity or protecting the customer data..." (Twitter: @ArigatoDamato)
Video: Execs We're Not Responsible for Cybersecurity
Laws and regulations have not kept pace with growth of Internet technologies.  No clear expectations have been communicated to the software industry or users of these services by policy makers.  Executives have responsibility for protecting customer data but enforcement remains selective.  In the most egregious incidents, top C-level execs have been terminated for poor cybersecurity (e.g., Target).

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