Tester's Digest

A weekly source of software testing news


ISSUE #4 - Feb 26th, 2017

This issue’s topic was prompted by this week’s news of the Cloudbleed security leak, and proof of successful attack on SHA1 encryption. Disclaimer: I’m not a security expert by any means, so caveat emptor.

Topic: Security Testing

A very good list of resources for security testing and more:


Security breaches and how to deal with them (an incident responder’s view, useful for testers too):


Extreme security testing, the Red Team approach at Facebook:


At the other end of the spectrum, beginner steps in checking for security vulnerabilities, using Fiddler as the tool:


How to reengineer a piece of software (in this case, TLS security protocol spec and implementation) for quality and testability:


Security questions (you know, “what was the name of your first pet?”) are deeply insecure, and what to do about it:



Don’t panic. The big security holes named this week - collision in SHA-1, and Cloudbleed leak - are not known to be exploited in the wild. Safeguard yourself calmly.

SHA-1 hash function, known to be insecure for years, is now proven as such: cryptographers from Google and SWI Institute intentionally generated a SHA-1 collision on two distinct PDF files (underlying code to be released after 90 days). If you were still using SHA-1 for PGP encryption or anything else, please stop.


SHAttered website has more practical details, including advice not to put those two PDFs into a Subversion repository, as that would break the svn server! They also offer a tester to validate if your files were part of a collision attack, with the promise that your uploaded files don’t get stored. To trust or not to trust…


Onto Cloudbleed: a Heartbleed-style buffer overflow bug in Cloudflare’s code resulted in HTTP responses including random snippets of information from unrelated sites backed by Cloudflare service (such as: Fitbit, Uber, OKCupid). Your passwords and other personal details may now be cached all over the interwebs. Incident report from Cloudflare itself:


As described by the discoverer from Google’s Project Zero:


For a shorter read, high level post with advice (to change all your passwords and use a password manager):



While you’re changing all those passwords in the wake of Cloudbleed, see if you want to run them through this “slightly evil password strength checker”. Don’t miss the inspirational xkcd.


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