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Disassembling network traffic into asm instructions v0.3.0

The fresh released version of haka (v0.3.0) features a new module allowing to disassemble network data into instructions. This is useful to detect obfuscated shellcodes at network level as suggested in [raid05]1 for instance. The disassembler leverages on Capstone engine which supports several architecture (x86, arm, mips, etc.).

Here we will try to answer to question 8 of a well-known network forensic challenge. The challenge provides a pcap and asks to dump the shellcode used to exploit a vulnerability and then to provide the list of actions done by this shellcode.

  1. [raid05] Kruegel, C., Kirda, E., Mutz, D., Robertson, W., Vigna, G.: Polymorphic Worm Detection Using Structural Information of Executables. In: Recent Advanced in Intrusion Detection, pp. 207-226 (2005)

Visualizing alerts using kibana and elasticsearch v0.2.1

As you have already noticed, haka 0.2.1 features new modules enabling to export data to an elasticsearch server. We leveraged on these modules in the Hakabana package to monitor in real-time network data (protocols, flows, geoip info, etc.) through a kibana dashboard.

The 0.2.1 version introduces also an elasticsearch alerting module allowing to insert haka alerts into an elasticsearch server. In the following, we present the main steps to visualize these alerts using a kibana dashboard.

kibana ips dashboard

Detecting Heartbleed with Haka v0.2

As most of you must have heard, a very nasty bug was discovered few weeks ago in the OpenSSL project, a widely used open source implementation of the SSL/TLS protocol. This bug which is better known as the heartbleed bug, relies on a wrongly implemented SSL extension called "heartbeat".

As you know, the initial version of Haka doesn't ship with a SSL dissector. However, the 0.2 version — which will be released soon — features a new grammar allowing to specify network protocols and their underlying state machine. Thanks to that grammar, we were able to write, with a little effort, a dissector covering almost the full specification of SSLv3 protocol. This specification will be covered in upcoming post.


Defeating Nmap Scans v0.1 v0.2

The well-known scanning tool Nmap allows users to discover running services on a target machine. In this tutorial, we use Haka to fool Nmap scans by crafting reset packets.

When launching a NULL (-sN), FIN (-sF) or XMAS (-sX) scan, Nmap forges a malicious packet with some flags activated. Nmap concludes that a port is closed on the target machine if it receives a RST packet.

Thanks to Haka API, we can forge RST packets and fool Nmap queries letting him think that all ports are closed on the target side. The following script starts by loading ipv4 and tcp dissectors. The next line disable the tcp-connection dissector to avoid Haka dropping all packets do not belonging to a valid connection. Finally, we define the secuity rule which will create a RST tcp packet if a nmap scanning packet is detected. In the last lines, we inject the newly crafted packet and drop the Nmap forged packet.

Interactive Packet Filtering Mode v0.1

Haka is endowed with an interesting feature allowing to filter packets interactively. With this mode activated, a Haka shell prompt is diplayed to the end-user which will have access to the full Haka API to play with packet content: accessing and modifying packet fields, dropping packets, logging suspicious events, alerting, etc. The Lua console supports auto-completion and therefore is a good starting point to dive into the Haka API.

SQLi Attack Detection v0.1

SQL injection attacks (SQLi) are common web attacks that consist in injecting SQL commands through http requests, enabling thus sensitive data disclosure or authentication scheme bypass. SQLi are the most dangerous software attacks according to the SANS Institute ranking.