Netresec is an independent software vendor with focus on the network security field. We specialize in software for network forensics and analysis of network traffic.
Our most well known product is NetworkMiner, which is available in a professional as well as free open source version. We also develop and maintain other software tools, such as CapLoader (for big pcap files) and RawCap (a lightweight sniffer).
We at Netresec additionally maintain a comprehensive list of publicly available pcap files.
NetworkMiner is a Network Forensic Analysis Tool (NFAT) for Windows. NetworkMiner can be used as a passive network sniffer/packet capturing tool in order to detect operating systems, sessions, hostnames, open ports etc. without putting any traffic on the network. NetworkMiner can also parse PCAP files for off-line analysis and to regenerate/reassemble transmitted files and certificates from PCAP files.
CapLoader is a Windows tool designed to handle large amounts of captured network traffic in the tcpdump/libpcap format (PCAP). CapLoader displays the contents of opened PCAP files as a list of TCP and UDP flows. Users can select the flows of interest and quickly filter out those packets from the loaded PCAP files. Sending the selected flows/packets to a packet analyzer tool like Wireshark or NetworkMiner is then just a mouse click away.
PolarProxy is a transparent SSL/TLS proxy created for incident responders and malware researchers. PolarProxy is primarily designed to intercept and decrypt TLS encrypted traffic from malware that is run in a controlled environment, such as a sandbox. PolarProxy decrypts and re-encrypts TLS traffic, while also saving the decrypted traffic in a PCAP file.
Additional software from Netresec can be found on our products page.
Sniffing Decrypted TLS Traffic with Security Onion
Wouldn't it be awesome to have a NIDS like Snort, Suricata or Zeek inspect HTTP requests leaving your network inside TLS encrypted HTTPS traffic? Yeah, we think so too! We have therefore created this guide on how to configure Security Onion to sniff decrypted TLS traffic with help of PolarProxy. Pol[...]
Sharing a PCAP with Decrypted HTTPS
Modern malware and botnet C2 protocols use TLS encryption in order to blend in with 'normal' web traffic, sometimes even using legitimate services like Twitter or Instagram. I did a live demo at the CS3Sthlm conference last year, titled 'TLS Interception and Decryption', where I showed how TLS inter[...]
Installing a Fake Internet with INetSim and PolarProxy
This is a tutorial on how to set up an environment for dynamic malware analysis, which can be used to analyze otherwise encrypted HTTPS and SMTPS traffic without allowing the malware to connect to the Internet. Dynamic malware analysis (or behavioral analysis) is performed by observing the behavior[...]
The NSA HSTS Security Feature Mystery
I recently stumbled across an NSA Cyber Advisory titled Managing Risk from Transport Layer Security Inspection (U/OO/212028-19) after first learning about it through Jonas Lejon's blog post NSA varnar för TLS-inspektion (Swedish). I read the NSA report with great interest since I wanted to see how o[...]
Extracting Kerberos Credentials from PCAP
NetworkMiner is one of the best tools around for extracting credentials, such as usernames and passwords, from PCAP files. The credential extraction feature is primarily designed for defenders, in order to analyze credential theft and lateral movement by adversaries inside your networks. But the cre[...]
NetworkMiner 2.5 Released
I am happy to announce the release of NetworkMiner 2.5 today! This new version includes new features like JA3 and parsers for the HTTP/2 and DoH protocols. We have also added support for a few older protocols that are still widely used, such as Kerberos and the CIFS browser protocol. Additionally, N[...]
Raspberry PI WiFi Access Point with TLS Inspection
This is a how-to guide for setting up a Raspberry Pi as a WiFi Access Point, which acts as a transparent TLS proxy and saves the decrypted traffic in PCAP files. Image: Raspberry Pi 4 Model B running PolarProxyStep 1: Install PolarProxy for Linux ARM We will start with installing PolarProxy, which w[...]