Automatic Mitigation of Meltdown

Let’s look at what Meltdown is and how it works, as well as how it is stopped. A lot has been written about the Meltdown vulnerability, but it is still commonly misunderstood. A few diagrams may help. First, let’s consider a simplified memory hierarchy for a computer: main memory, split into user memory and kernelContinue reading “Automatic Mitigation of Meltdown”

Convert between Docker Registry Credentials, K8s Image Pull Secrets, and config.json live

Generating registry secrets for Kubernetes is cumbersome. Extracting creds or updating the secret is annoying. Generating config.json is painful. But we need to do it all the time! https://polyverse.github.io/docker-creds-converter/ I frequently generate service accounts in our private image hub for various tests. Generating config.json is cumbersome. Injecting that into a kubernetes cluster as a registry secretContinue reading “Convert between Docker Registry Credentials, K8s Image Pull Secrets, and config.json live”

ASLR simplified!

ASLR explained in one simple picture ASLR increases difficulty without adding complexity. In Part 1 and Part 2 of this series I demonstrated that crafting attacks can be a pleasant experience without a lot of furious typing. I’ve even shown you how defeating exploits is easy when we really understand how the attack works. LetsContinue reading “ASLR simplified!”

Fun with binaries!

ASLR and DEP defeated with three instructions and one offset! This is Part 2 of my previous post that demonstrated how you craft undetectable attacks against binaries, using our colorful Open Source Entropy Visualization tool. I left you with a cliffhanger… so let’s begin there! Recap of the cliffhanger The cliffhanger I left you withContinue reading “Fun with binaries!”

Let’s craft some real attacks!

If you read security briefings, you wake up every morning to “buffer overflow” vulnerabilities, “control flow” exploits, crafted attacks against specific versions of code, and whatnot. Most of those descriptions are bland and dry. Moreover, much of it makes no intuitive sense, everyone has their fad of the week, and it is easy to feelContinue reading “Let’s craft some real attacks!”

Semantic Versioning has failed Agile

This is an Engineering post on how we build software at Polyverse, what processes we follow and why we follow them. A couple of weeks ago, I attended a CoffeeOps meetup at Chef HQ. One of my answers detailing how we do agile, CI/CD, etc. got people excited. That prompted me to describe in detailContinue reading “Semantic Versioning has failed Agile”

Calling deco at the first Deco Stop

Disclaimer: These numbers are most certainly “WRONG!” You should NOT use this post or anything from a random only tool to plan or execute dives. You WILL get bent. Not “may”, but WILL. You know this. DO NOT rely on this tool. Here’s a scenario that should never happen, but to quote the eloquent Mr. Mackey, “ThereContinue reading “Calling deco at the first Deco Stop”

Recipes to play with “No Deco Limits”

For a technical, philosophical and every other view on No-Deco limits, go to scubaboard. First let me elaborate on why the mathematical model is important and how to play with it. Models allow reverse engineering (fitting) This post is about understanding the mathematical model in terms of the NDLs we know and use. One of theContinue reading “Recipes to play with “No Deco Limits””

Dive Planner Recipes

This is really for my personal reference. If it helps you, I’m glad. A couple of weeks ago, I wrote this tool (http://deco-planner.archisgore.com.) You can go read the history, motivation, etc. on that page and the github repo ad nauseum. NOTE: Why is this important/useful? Don’t computers tell you how much deco you should do?Continue reading “Dive Planner Recipes”

Scuba Diving tools

At some point I made a page to document random scuba tools I build/will-build/want-to-build/want-others-to-build. The last part is a bit tricky. I want many things – and asking others to build something is painful. You don’t always get what you want. You don’t always like what you get. You don’t always get what you want,Continue reading “Scuba Diving tools”