Application Security Weekly for May 27

Portswigger (who builds Burp Suite) has a great article about finding vulnerabilities in bug bounty programs.  Must read.


SANS has a great article about Antivirus evasion.  Don't try this at home.


Oh hey I almost forgot about this one.  Remember that Electron bug that was patched?  It didn't work.  Patch again.

(Maybe we shouldn't write Windows apps in JavaScript.  Hmm.)


REALLY cool use of HTML5 to attack iOS.  NEat stuff, good writeup.


And that's the news.


Application Security Weekly for May 20

Pretty big encryption news this week.  A well known flaw in HTML emails that are encrypted with S/MIME or PGP was "discovered" by some researches, and given the full name, website, and logo treatment.  Even the EFF chimed in and astonishingly suggested people uninstall their encryption tools. The risk was largely overblown; take a look at the #efail tag on Twitter.  Here are a few links that give part of the story.


Have you updated your Electron app?  Hope so - there was a pretty bad code-injection flaw.


Pro tip: Don't hardcode passwords into your devices.  Full stop.


A bug in cell phone tracking firm's website leaked millions of Americans' real-time locations


And that's the news.


Application Security Weekly for May 13

Thousands of Companies Are Still Downloading the Vulnerability That Wrecked Equifax


Another fun iOS bug - The Black Dot of Death


The Nest doorbell doesn't invalidate existing OAUTH refresh tokens when the password is changed.  How could they miss that?


Introducing Throwhammer - Rowhammer over the network


And that's the news.


Telling Developers About Vulnerabilities Isn't Enough

To many security firms, a web application vulnerability assessment is a list of confirmed exploitable findings in a web application.  They index the site, run scans, manually test, so research, and write them all down.  The report will get you through a PCI audit.

That's not enough.  You must tell the developer how to fix the problem, and "apply patches" isn't enough.  If you find cross-site request forgery, and can't explain the developer how to fix the problem on their platform, you aren't doing enough.  "Add a token" isn't enough.  "Apply fix as appropriate for your language" isn't enough.  If you don't know, that's fine, but learn.  

We are, as an industry, doing a tremendous disservice to companies by selling them 68 pages of non actionable fluff for $10,000.  If you, as a tester, aren't sure how to fix it, look it up, ask someone, or work directly with the developer to find a solution.

Application Security Weekly for May 6

Good intro to fingerprinting web servers.  This has been codified in the past but the tools are all old.  Need to resurrect an open source project.


I mentioned CVE-2018-2628 and my Nikto test for it in an earlier newsletter.  Well, apparently the patch doesn't work.


Nice video of finding and exploiting another hole in the PDF format.  Apparently they are so common now we just livestream them.


I am fond of saying that the government can outlaw as much encryption as they want, if the bad guys have two coins and a pencil, they can make as much unbreakable encryption as they want with a one-time pad. (Not my line and I don't remember the source sorry)  Here is another nice new pencil and paper cipher.


Finally.  PHP has a security flaw.  WHAT YEAR IS IT??


And that's the news.

Base64 is not encryption

I posted a silly tweet after finding a vulnerability in an Android app the other day.  It grew legs and is making its way around.



I've gotten a few funny replies, but not as good as the QA tweet - mostly "Well duh" or "It isn't" or "People think that?" So I wanted to write a short explainer.

Base64 looks like encryption.  The nice readable test gets all scrambled up.  For instance the text of the tweet turns into this:


See, not even spaces!  Wild stuff!  But it is not encrypted.  Base64 encoding is a way to turn binary or ANSI files into something that can be transferred over a readable ASCII only medium like the web.  For instance, your binary serialization is like that. If you serialize an object and save it, you'll have unreadable characters in there.  If you base64 encode it, you can save it in a cookie of a web page.  It's super handy, but it is not protected.  The page I used to encode the example above is here:

So to give a concrete example, if you use Apache MyFaces or ASP.NET Web Forms (pre 4.6.2) then your viewstate is just Base64 encoded.  Don't believe me?  View source, find the viewstate, and paste it into the site above.  It will probably decode for you. An attacker can change that data and resubmit, so take care!

To learn even more, check out the OWASP Cryptography cheat sheet.


Application Security Weekly for April 29

My favorite thing this week, how HTTPS works, via a cartoon of cats.


Ray Ozzie (yeah, that Ray Ozzie) says he has a solution for backdoorable encryption.


Tutorial by Check Point on stealing NTLM hashes with weaponized PDF files.  Check your file upload features, folks!


And that's the news!

Application security weekly for April 22

More news than usual today.


There is a new WebLogic RCE. I'll be adding it to Nikto this week.


Android is adding DNS over TLS. As a user I am happy about this.  As a tester, @#$%&#$%@^.


There are 100 devs for every appsec specialist.  We have out work cut out for us.


The thermometer in a fishtank was the pivot point for hackers to pwn a casino. Noice.


Holy crap I forgot about this one.  The RSA custom Android application had the API keys stored in the source code, so someone downloaded the attendee list.


Verizon last week, Microsoft this week. Annual security report.


Finally, a teen found some documents on a web server, downloaded them, and now is going to jail.  Stay safe out there kids!


And that's the news.

Application Security Weekly for April 15

The Verizon Data Breach Investigations Report is out. It's a good read.


DARPA (the government organization that created the Internet) is funding research into Human Assisted AI.


WebAuthN went to Candidate stage, perhaps leading to the end of passwords on the Internet.  But ... universal federal IDs?  Not sure.


Motherboard has a REALLY good series on phone cracking.  If you are into mobile, it's worth a look.


And that's the news


Some neat events I'll be participating in this spring

There are some neat developer and security events this spring that I'll be speaking at or otherwise participating in, and I'd love to see all of you there!

On the morning of the 18th, I'll be talking about updated OWASP Projects at the Columbus ISSA meeting.  I know daytime meetings are weird, but come by if you can. There is a small charge for non-members.

April 26th, there is an OWASP meetup where we will be following up on Jason Kent's Docker seminar and building some cool python code. This event is at the Idea Foundry, and is a lab environment - bring your machine. I'll get everyone started, but this is mostly team coding.

In May, on the 4th, I'll be speaking about the changes to the OWASP Top 10 at Stir Trek, one of the most awesome developer events in the midwest. The content is awesome, the venue is a movie theater, and you get to watch the new Avengers movie the night before the rest of the world! NO SPOILERS.

May 14th, I have the honor of speaking at one of the most awesome security events in the midwest (I told you this was quite a spring!) It's the Central Ohio InfoSec Summit, and the content is also awesome, although there isn't a movie at the end. If you can go, do so.  It's really a great conference.

Gonna be a bust few months, but some really great events.  Make sure you catch what you can - attending these events is one of the best ways to stretch your mind and see what skills you should be working on right now.

Bill Sempf

Husband. Father. Pentester. Secure software composer. Brewer. Lockpicker. Ninja. Insurrectionist. Lumberjack. All words that have been used to describe me recently. I help people write more secure software.



profile for Bill Sempf on Stack Exchange, a network of free, community-driven Q&A sites