Online banking security

Checkmarx interviewed me for their article ‘All You Wanted To Know About Online Banking Security’:

checkmarx 2

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NOS: “Wat vind je van de nieuwe hackersserie Mr. Robot?”

Benieuwd wat ik van de nieuwe hackersserie Mr. Robot vind? De NOS vroeg het mij:

nos 2

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Inbreken in de NOS-studio?

Dit keer is een hacker het wel gelukt om in de juiste NOS-studio te komen ;-)


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Interviewed by Lock Me Down podcast

Max McCarty from Lock Me Down podcast interviewed me for an hour (view the show notes) and we talked about web security and how software developers can improve it:

Posted in podcast, security awareness, software development, website security | 1 Comment

Zo slordig gaan bedrijven met persoonsgegevens van hun klanten om

Nieuwssite Z24 had een interview met mij en heeft hierover een uitgebreid artikel geschreven:

z24 2

Posted in interview, security awareness | 5 Comments

Interview op BNR Nieuwsradio

Vanmiddag had BNR Nieuwsradio mij uitgenodigd in hun radioprogramma over het wachtwoordlek dat ik gevonden had bij Phone House en Media Markt. De uitzending is online terug te beluisteren:


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Epic failure of Phone House & Dutch telecom providers to protect personal data: How I could access 12+ million records #phonehousegate

On September 11, 2015 I visited Media Markt in Utrecht Hoog Catherijne, a well-known electronics shop in The Netherlands. Since summer 2014, the biggest independent Dutch phone retail company Phone House also operates (white labeled) from within Media Markt locations as a store-in-a-store concept. I had a few questions about my phone subscription so I talked to a Phone House employee. We were discussing the new Samsung Galaxy S6 Edge phone and I was thinking about buying one.

Somewhere in the conversation the service & sales guy asked me what I did for a living so I told him I earned my money as a freelancer by hacking (with authorization) into computer systems of businesses and writing security reports about it. He thought that was cool so we talked a few more minutes about this subject. I even told him I had noticed some months ago that one of his Media Markt colleagues had written a password on a post-it and attached it onto a computer monitor near a cash desk, in plain sight where any customer could see it :

tn_20151003_171315(0) v3 Naamloos

As you can see, the password to unlock Media Markt computers was media321. A very strong one!

We both laughed about how irresponsible and naive that was.

The conversation continued about my desire for a new phone and about all associated kinds of subscriptions I could choose of. After about ten minutes I made up my mind and ordered a new phone and a new subscription. I’m still in shock about what happened next! Continue reading

Posted in data leakage, privacy, responsible disclosure, security assessment | 419 Comments

Scanning an enterprise organisation for the critical Java deserialization vulnerability

On November 6, security researchers of FoxGlove Security released five zero day exploits for WebSphere, WebLogic, JBoss, Jenkins and OpenNMS. These software products are used everywhere in enterprise organizations and with the published exploits remote malicious code can be unauthenticated executed.

The underlying vulnerability was known for years but it was vague and believed to be hard to exploit. That situation changed when Chris Frohoff (@frohoff) and Gabriel Lawrence (@gebl) published in January of an exploit generator for it in their talk on AppSecCali . Their generator didn’t get much attention on the internet. FoxGlove didn’t find the original (underlying) vulnerability, but they did find vulnerable products and wrote exploits for it. They call the vulnerability “the most underrated, underhyped vulnerability of “. When I read about FoxGlobe’s research on Twitter on November 8, , my guts told me immediately that this was something big. Continue reading

Posted in analysis, security vulnerability, zero day | 25 Comments

How I could hack internet bank accounts of Danish largest bank in a few minutes

In August I visited the Chaos Communication Camp near Berlin. Once every four years this great and world’s greatest hacker festival is organized. I spoke with a couple of cool Danish hackers there and we talked about internet security and eventually about the security of Danish banks. Seemed like quite a lot of Danish bank have terrible HTTPS connection security (scoring a F on Qualys SSL Labs). That’s a bad sign and my gut feeling was telling me that this wouldn’t be the only security vulnerability they would have.

So I opened up the web site of Danske Bank, one of those bank sites. I clicked thru the site and was curious to see how the HTML code looked like, so opened the code of the customer login screen of the banking environment. I scrolled thru the code to get a grasp of the technology used. Then my eye caught JavaScript comments that seemed to contain internal server information. Not just a few variables, but quite a lot of confidential data actually (!). It was in URL encoded format, so I decoded it right away. Really wondering what kind of secrets it contained.

When I decoded it, I was shocked. Is this happening for real? I was less than a minute on their web site. This is just the HTML code of the login screen, one of the most visited pages of Danske Bank’s web site. I never heard of this bank, but my new friends told me it was the biggest bank in Denmark. Continue reading

Posted in responsible disclosure, website security | 183 Comments

Full disclosure: multiple critical security vulnerabilities (including a backdoor!) in PHP File Manager

In July 2010 I was looking for a web based file manager that I could use on my own web server. After some research I found the PHP File Manager from Revived Wire Media. A basic, but good looking web based file manager for just $ 5. I bought it and installed it on a test server to see how it worked and if it was safe.

After looking at it, I did some shocking findings which I’ll disclose in this article. This commercial off the shelf software product contains several critical security vulnerabilities that can be easily unauthenticated remotely exploited. On top of that, it even includes a poorly secured backdoor, leaving this web based file manager completely open.

I’ve contacted Revived Wire Media three times but got no response of them, so I’m going full disclosure.

At this moment, confidential files can be be easily downloaded from Eneco, Nintendo, Danone, Nestle, Loreal, EON, Siemens, Vattenfall, Oxford, Hilton, T-Mobile, CBS, 3M and also a couple of banks and quite a lot of other companies (lesser known to me).

One company in America that uses the file manager is active in youth care and provides mental health and substance abuse services. It has 250 mental health professionals who are probably sharing all kinds of very confidential patient information via PHP File Manager.

Continue reading

Posted in PHP security, responsible disclosure, security assessment | 36 Comments

M-FILES radioshow: ‘Rest In Privacy’

Deze week was ik te gast in de radioshow van M-FILES wat ging over online privacy. Vanaf 22:12 minuten is mijn bijdrage te horen:

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Lukt het om in te breken in de website van Massa Media?

Die vraag stelde een TV-ploeg van RTV Utrecht mij:

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Security risk analysis of address bar spoofing bug in Chrome and Opera

On June 30, 2015 security researcher David Leo publicly disclosed a vulnerability in Google Chrome on the full disclosure mailing list. Via this vulnerability it is possible to spoof the location of the address bar in the latest version of Chrome.

The team behind Chrome has been notified by the researcher of this issue via responsible disclosure. Google thought it wasn’t a serious issue and thus they haven’t patched it (yet?). Google classified the bug as a denial of service vulnerability. As a result, the security researcher decided to fully disclose all the details of the vulnerability, including a working exploit, in order to gain attention to the problem.

This week this vulnerability was broadly discussed within the security scene and there were a lot of different opinions and no clear threat analysis was made. I hope to add something to that discussion with my analysis. Continue reading

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De wereld van hacking

Gisteren heb ik onderstaande presentatie gehouden op het Privacy & Security symposium van hogeschool Windesheim:

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Mitigations against critical universal cross-site scripting vulnerability in fully patched Internet Explorer 10 and 11

This week David Leo disclosed a critical universal cross-site scripting vulnerability in fully patched Microsoft Internet Explorer 10 and 11 (from now on called the UXSS leak). He notified Microsoft on October 13 last year, but Microsoft didn’t publish a patch for the problem, so he decided to go full public disclosure on the Nmap mailing list.

Every web site you visit with Internet Explorer version 10 and 11 can read the contents of cookies from other domain names that the user has stored in their web browser. An attacker can circumvent the same-origin policy via the UXSS leak. This is a primary and very important security measure in all browsers. It prevents web sites from reading each others data. And as of speaking, this protection is now completely broken in Internet Explorer 10 and 11. Continue reading

Posted in browser security, cross site scripting, security vulnerability, website security | 1 Comment

Cross-site scripting in millions of web sites

In August 2014 I found a severe cross-site scripting security vulnerability in the latest version (1.13.0) of the ‘jQuery Validation Plugin‘ during a security penetration test for a customer. This jQuery plugin which adds easy form validation functionality to a web site, is written by a core developer of the highly popular jQuery JavaScript framework.

As of speaking this vulnerability still exists and hasn’t been patched. Continue reading

Posted in cross site scripting, Google, PHP, responsible disclosure | 62 Comments

2.364 Nederlandse bedrijfswebsites met ernstige beveiligingslekken

Toen ik in oktober 2012 op internet op zoek was naar een nieuwe auto, kwam ik een autobedrijf tegen waar ik een auto wou gaan kopen:

1-v2(bovenstaande website is van een willekeurig bedrijf uit de lijst die ik later beschrijf)

Omdat ik het nogal eng vind om bij een via het internet gevonden bedrijf een auto te gaan kopen, heb ik lichtelijk en oppervlakkig naar de website gekeken van de aanbieder. Kijkend naar aanwijzingen die duiden op oplichting of fraude. Je weet maar nooit. Continue reading

Posted in responsible disclosure, search engine optimization, security vulnerability, website security | 15 Comments

Password hash disclosure in Linksys Smart WiFi routers

This is my tale about reporting a specific security vulnerability in a major product, just to give some insight in how responsible disclosures are handled by a security researcher (me) and various software companies (Cisco, Linksys and Belkin).

On May 17 in 2013 I found a severe password hash disclosure in a Cisco Linksys EA6700 router. At that time this was the top model that Linksys had to offer for consumers. The router is a Linksys Smart WiFi router. Continue reading

Posted in password, responsible disclosure | 5 Comments

Wat te doen tegen hard coded databasewachtwoorden in configuratiebestanden?

Kreeg vandaag de volgende vraag binnen waarvan mijn antwoord ook voor anderen nuttig kan zijn:

Is er een beveiligingsoplossing tegen hard coded databasewachtwoorden, zoals bijvoorbeeld het geval is bij websites die in de programmeercode het MySQL-wachtwoord in een configuratiebestand hebben opgeslagen? Wanneer dit wachtwoord in verkeerde handen valt, dan heeft een kwaadwillend persoon direct de kroonjuwelen van de database in handen. Kan asymmetrische encryptie of kunnen certificaten eventueel uitkomst bieden?

Dit is een goeie vraag. Helaas is er niet echt een oplossing. Het wachtwoord is namelijk de toegangspoort tot MySQL en dus niet uit te bannen. MySQL is hierin niet uniek als platform. Wachtwoorden zijn als authenticatiemiddel een noodzakelijk kwaad om toegang tot allerlei services te krijgen. Algemeen gesproken is er geen heiligmakende oplossing tegen hard coded wachtwoorden. Wel zijn mitigerende maatregelen te nemen. Continue reading

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Test voor vatbaarheid op afstand wissen van alle gegevens op een mobiele telefoon

Heb een test online gezet waarmee je kan controleren of je mobiele telefoon vatbaar is voor het op afstand wissen van al je gegevens op je telefoon (door het bezoeken van een kwaadaardige website). De test is onschuldig en laat alleen het unieke IMEI-nummer van je telefoon zien.

Als je een Samsung telefoon hebt, dan valt het *sterk* aan te bevelen de test uit te voeren.

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