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NetworkMiner 2.6 Released

NetworkMiner 2.6

We are happy to announce the release of NetworkMiner 2.6 today! The network forensic tool is now even better at extracting emails, password hashes, FTP transfers and artifacts from HTTP and HTTP/2 traffic than before.

Some of the major improvements in this new release are related to extraction and presentation of emails from SMTP, POP3 and IMAP traffic. On that note, we’d like to thank Mandy van Oosterhout for reporting a bug in our email parser!

Emails extracted with NetworkMiner 2-6
Image: Emails extracted from SMTP and IMAP traffic

I have previously blogged about how to extract John-the-Ripper hashes from Kerberos network traffic with NetworkMiner. We have now added support for presenting LANMAN and NTLM credentials as JtR hashes as well.

NTLMv2 and Kerberos hashes in NetworkMiner 2.6
Image: JtR formatted NTLMv2 and Kerberos hashes in NetworkMiner 2.6

We have also improved NetworkMiner’s Linux support. Files, images and folders can now be opened in external tools directly from the NetworkMiner GUI also when running NetworkMiner in Linux using Mono 6 (or later). Linux users previously got a “System.ComponentModel.Win32Exception” error message saying something like “Cannot find the specified file” or “Access denied” due to a breaking change introduced in Mono version 6.

NetworkMiner running in Ubuntu 20.04
Image: NetworkMiner 2.6 running in Ubuntu 20.04 with Mono 6.8.0.105

The new release also comes with several updates of how HTTP and HTTP/2 traffic is handled and presented. We have, for example, added better extraction of data sent in HTTP (or HTTP/2) POST requests. Posted JSON formatted parameters are also extracted even if the JSON data has been gzip compressed. The “Accept-Language” header values in HTTP and HTTP/2 are extracted as “Host Details” in order to support forensic analysis of user language settings, as shown by Fox-IT in their “Operation Wocao - Shining a light on one of China’s hidden hacking groups” report.

NetworkMiner has supported decapsulation of tunneling protocols and protocols for network virtualization, like 802.1Q, GRE, PPPoE, VXLAN, OpenFlow, MPLS and EoMPLS, since version 2.1. We have now improved our GRE parser to also support NVGRE (RFC 7637) by adding support for Transparent Ethernet Bridging.

Jan Hesse sent us a feature request on Twitter earlier this year, where asked about support for FritzBox captures. We are happy to announce that NetworkMiner now supports the modified pcap format you get when sniffing network traffic with a FritzBox gateway.

Fritz!Box

NetworkMiner 2.6 can now also parse and extract SIP chat messages (RFC 3428) to the “Messages” tab. Audio extraction of VoIP calls is still a feature that is exclusively available only in NetworkMiner Professional though.

NetworkMiner Professional

Our commercial tool NetworkMiner Professional has received a few additional updates, such as support for analysis of HTTP/2 traffic in the “Browsers tab”. However, please note that NetworkMiner does not perform TLS decryption, so the HTTP/2 traffic will have to be decrypted by a TLS proxy like PolarProxy prior to being saved to a PCAP file.

HTTP/2 traffic in NetworkMiner Professional's Browsers tab

We have added a few new great online services to NetworkMiner Pro’s OSINT lookup as well, such as shouldiclick.org, Browserling, MalwareDomainList and VirusTotal lookups of URL’s in the “Browsers” tab. We have also added some additional external OSINT sources for lookups of IP addresses and domain names, such as MalwareDomainList and mnemonic ACT. The JA3 hash lookup menu in NetworkMiner Professional’s “Hosts” tab has also been extended to include GreyNoise.

URL lookup menu in NetworkMiner Professional's Browsers tab

NetworkMiner Pro previously played back G.722 VoIP audio at half speed. This issue has now been fixed, so that G.722 RTP audio is extracted and played back in 16k samples/s. The bug was due to an error in RFC 1890 that was later corrected in RFC 3551. Thanks to Michael "MiKa" Kafka for teaching us about this!

Excerpt from RFC 3551:

Even though the actual sampling rate for G.722 audio is 16,000 Hz, the RTP clock rate for the G722 payload format is 8,000 Hz because that value was erroneously assigned in RFC 1890 and must remain unchanged for backward compatibility. The octet rate or sample-pair rate is 8,000 Hz.

We’d also like to mention that NetworkMiner Professional now comes with improved analytical support to help investigators detect Tor traffic.

Upgrading to Version 2.6

Users who have purchased a license for NetworkMiner Professional 2.x can download a free update to version 2.6 from our customer portal, or use the “Help > Check for Updates” feature. Those who instead prefer to use the free and open source version can grab the latest version of NetworkMiner from the official NetworkMiner page.

Posted by Erik Hjelmvik on Wednesday, 23 September 2020 09:10:00 (UTC/GMT)

Tags: #NetworkMiner#SMTP#POP3#IMAP#email#FTP#JtR#John#Mono#Linux#HTTP#HTTP/2#JSON#GRE#SIP#VoIP#Tor#PCAP

Short URL: https://netresec.com/?b=209ff4e


Extracting Kerberos Credentials from PCAP

NetworkMiner + Cerberos

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 credential extraction feature is also popular among penetration testers. In this blog post I will demo how Kerberos hashes can be extracted from captured network traffic with NetworkMiner, and how these hashes can be cracked in order to retrieve the clear text passwords.

Installing NetworkMiner in Kali Linux

I’m using a clean install of Kali Linux 2019.3, on which I have installed NetworkMiner by following the step-by-step instructions in our guide for installing NetworkMiner in Ubuntu, Fedora and Arch Linux.

NetworkMiner 2.5 in Kali Linux

Extracting Kerberos Hashes from PCAP

There is a capture file in Wireshark’s sample captures called krb-816.cap. This capture file contains Kerberos traffic from a Windows XP machine, as two user accounts perform a domain logon. Let’s download that PCAP file and open it in NetworkMiner.

wget 'https://wiki.wireshark.org/SampleCaptures?action=AttachFile&do=get&target=krb-816.zip' -O krb-816.zip
unzip krb-816.zip
/opt/NetworkMiner_2-5/NetworkMiner.exe krb-816.cap

The “Credentials” tab contains the extracted Kerberos hashes. Right-click on the first $krb5pa$23$ hash and select “Copy Password” to put the password into the system clipboard.

Copy Kerberos hash to system clipboard in Linux

Paste the password to a text file, either using a text editor or directly from a shell.

Note: You'll need to do press Ctrl+Shift+Insert in GNOME Terminal to paste from the system clipboard, which is where NetworkMiner has put the password.

echo '$krb5pa$23$des$DENYDC$$32d396a914a4d0a78e979ba75d4ff53c1db7294141760fee05e434c12ecf8d5b9aa5839e09a2244893aff5f384f79c37883f154a' > krb5pa.hash

You can now try to crack the hash, for example by running John the Ripper (JtR) or hashcat.

john krb5pa.hash
Using default input encoding: UTF-8
Loaded 1 password hash (krb5pa-md5, Kerberos 5 AS-REQ Pre-Auth etype 23 [32/64])
[...]
Use the "--show" option to display all of the cracked passwords reliably
Session completed
john krb5pa.hash --show
?:123

1 password hash cracked, 0 left

Yay! We now know that the password of user “des” was “123”. Let’s try to recover the password of the user “u5” as well, but this time we’ll use the $krb5asrep$23$ hash.

Copying the krb5asrep hash from NetworkMiner
john krb5asrep.hash
[...]
john krb5asrep.hash --show
?:123

1 password hash cracked, 0 left

Apparently the password for user u5 was “123” as well.

If you wanna replace JtR with hashcat, then make sure to use the following hash modes:

  • $krb5pa$23$: hashcat -m 7500
  • $krb5tgs$23$: hashcat -m 13100
  • $krb5asrep$23$: hashcat -m 18200
For other hash types, please see the hashcat example hashes.

Running the Command Line version of NetworkMiner

The commercial version of NetworkMiner comes with a command line tool called NetworkMinerCLI. You can extract the Kerberos hashes from a PCAP file and save them to a CSV file using NetworkMinerCLI like this:

/opt/NetworkMinerProfessional_2-5/NetworkMinerCLI.exe -r krb-816.cap -f CSV_NoNewlines
Closing file handles...
32 frames parsed in 0.1337 seconds.

NetworkMinerCLI has now created a set of CSV files, one for each type/class of information found in the capture file. In this case we want the krb-816.cap.Credentials.csv file, in which the hashes and passwords are in column 5:

cut -d, -f5 krb-816.cap.Credentials.csv
"Password"
"$krb5pa$23$des$DENYDC$$32d396a914a4d0a78e979ba75d4ff53c1db7294141760fee05e434c12ecf8d5b9aa5839e09a2244893aff5f384f79c37883f154a"
"$krb5pa$3$des$DENYDC$DENYDC.COMdes$233b4272aa93727221facfdbdcc9d1d9a0c43a2798c810600310c0daf48fb969c26cb47d69f575a65e00163845f68811f9c5266271cc0f91"
"$krb5asrep$3$DENYDC.COMdes$edbcc0d67f3a645254f086e6$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"
[...]

Posted by Erik Hjelmvik on Thursday, 14 November 2019 12:25:00 (UTC/GMT)

Tags: #PCAP#Kerberos#Linux#hashcat#John#JtR#NetworkMinerCLI

Short URL: https://netresec.com/?b=19B60ac


NetworkMiner 2.5 Released

NetworkMiner 2.5

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, NetworkMiner can now parse PCAP files up to twice as fast as before!

Improving Passive TLS Analysis with JA3

Almost all web traffic is TLS encrypted nowadays, which prevents incident responders, analysts and investigators from inspecting otherwise unencrypted HTTP traffic for clues about malicious behavior or criminal intent. This requires analysts to use alternative approaches, such as looking at hostnames and X.509 certificates. This type of analysis is supported by NetworkMiner, since it parses Server Name Indication fields in client TLS handshakes and extracts X.509 certificates automatically when PCAP files are loaded.

In this release we’ve also added support for another passive TLS analysis technique called JA3, which is a method for fingerprinting TLS client implementations.

NetworkMiner leverages the JA3 fingerprint database from Trisul Network Analytics in order to match observed JA3 hashes to hashes of known malware and “normal” applications. This is what it looks like when the capture file “snort.log.1428364808”, from the FIRST 2015 “Hands-on Network Forensics” training (available here), has been loaded into NetworkMiner 2.5:

JA3 fingerprint of a Skype client

Image: JA3 fingerprint of a Skype client in NetworkMiner 2.5

The JA3 hash is also available in the “Parameters” tab, which is useful in order to find out what hosts that particular TLS implementation was reaching out to.

Filtering on JA3 hash 06207a1730b5deeb207b0556e102ded2 in NetworkMiner 2.5

Image: Filtering on JA3 hash 06207a1730b5deeb207b0556e102ded2

HTTP/2 and DoH Support

Passive analysis of TLS traffic, such as HTTPS, often doesn’t give sufficient visibility. Many organizations therefore use TLS proxies in order to decrypt the traffic going in and out from their networks. However, more than half of all HTTPS traffic is actually http2 (RFC 7540) nowadays. This has previously been an issue for users who wanted to analyze decrypted http2 traffic from their TLS intercepting proxies with NetworkMiner. We’re happy to announce that NetworkMiner now can parse http2 traffic, that has been decrypted by a TLS proxy, and extract files from the http2 transfers.

NetworkMiner 2.5 also supports the DNS over HTTPS (DoH) protocol (RFC 8484), which is a technique for sending DNS queries as http2 POST requests and parsing the returned data as DNS responses. We’ve incorporated the DoH data into NetworkMiner’s DNS tab, so that you can analyze it just like normal DNS traffic.

DoH traffic to mozilla.cloudflare-dns.com in NetworkMiner’s DNS tab

Image: DoH traffic to mozilla.cloudflare-dns.com in NetworkMiner’s DNS tab

Please note that NetworkMiner 2.5 does not perform TLS decryption. This means that NetworkMiner can only parse the contents of a TLS stream if it has been decrypted by a TLS proxy, such as PolarProxy.

Extracting Kerberos Hashes from PCAP

NetworkMiner’s support for the Kerberos protocol allows you to passively track which user accounts that are authenticating to what services, simply by monitoring network traffic. This is a feature is essential in order to track credential theft and lateral movement by adversaries inside your networks. After implementing kerberos username and hash extraction we realized that this feature could also be valuable for penetration testers. We therefore decided to present extracted Kerberos credentials in a format that is compatible with tools like hashcat and John the Ripper.

Kerberos krb5pa, krb5asrep and krb5tgs credentials extracted from the Wireshark sample capture file

Image: Kerberos krb5pa, krb5asrep and krb5tgs credentials extracted from the Wireshark sample capture file Krb-contrained-delegation.cap

For more information about Kerberos hashes, please see our Extracting Kerberos Credentials from PCAP blog post.

Even more NetBIOS and CIFS Artifacts!

NetworkMiner is a popular tool for extracting files transferred over SMB and SMB2 from capture files. It can also extract a great deal of information about the communicating hosts from protocols like NetBIOS and SMB/CIFS, but earlier this year Chris Raiter notified us about an important piece of information that was missing in NetworkMiner: NetBIOS Name Service (NBNS) lookups and responses!

Detection and export of NBNS packets request on twitter

A couple of months later Dan Gunter sent us another great feature request for another protocol that runs on top of NetBIOS: the CIFS Browser Protocol (aka MS-BRWS).

We’re happy to announce that NBNS queries and responses are now shown in NetworkMiner’s Parameters tab, and details like hostnames, domain names, Windows versions and uptime us extracted from the MS-BRWS protocol. See the screenshots below, which were created by loading the capture file “case09.pcap” from Richard Bejtlich’s TCP/IP Weapons School 2.0 Sample Lab into NetworkMiner 2.5. Thanks for sharing Richard!

Hostname, domain and Windows version extracted from MS-BRWS traffic

Image: Hostname, domain and Windows version extracted from MS-BRWS traffic

NBNS queries and responses in NetworkMiner’s Parameters tab

Image: NBNS queries and responses in NetworkMiner’s Parameters tab

Mono 5 Required for Linux and MacOS

Linux and MacOS users, who run NetworkMiner with help of Mono, will need to ensure they have Mono 5 (or later) installed in order to run NetworkMiner 2.5. We recommend using at least Mono 5.18.

Instructions for installing NetworkMiner on Linux can be found in our blog post ”HowTo install NetworkMiner in Ubuntu Fedora and Arch Linux”.

MacOS users can refer to our “Running NetworkMiner on Mac OS X” blog post.

Users who are unable to install Mono 5 are recommended to use the old NetworkMiner 2.4 release, which can be downloaded here:
https://www.netresec.com/?download=NetworkMiner_2-4

NetworkMiner Professional

Apart from the features mentioned so far, our commercial tool NetworkMiner Professional now comes with a few additional new features. One of these features is port independent identification of RDP traffic, so that mstshash credentials can be extracted from RDP sessions even if the service doesn’t run on port 3389. The OSINT lookup context menus in NetworkMiner Professional have also been enriched with the following online services:

Several new features have also been included in the command line tool NetworkMinerCLI, including:

  • Recursive loading of PCAP files with the "-R” switch.
  • Configurable export types (hosts, files, DNS etc) with the “-x” switch.
  • Relative paths in CSV, XML and JSON/CASE exports unless the “-- absolutePaths” switch is used.

Credits

I’d like to thank Dan Gunter, Chris Raiter, Chris Sistrunk and a few more (who I cannot mention here) for contributing with feature requests and bug reports that have helped improve NetworkMiner.

Upgrading to Version 2.5

Users who have purchased a license for NetworkMiner Professional 2.x can download a free update to version 2.5 from our customer portal, or use the “Help > Check for Updates” feature. Those who instead prefer to use the free and open source version can grab the latest version of NetworkMiner from the official NetworkMiner page.

Posted by Erik Hjelmvik on Thursday, 07 November 2019 11:45:00 (UTC/GMT)

Tags: #NetworkMiner#JA3#HTTP/2#http2#DoH#Kerberos#NetBIOS#PCAP#hashcat#John#NetworkMinerCLI#OSINT

Short URL: https://netresec.com/?b=19B4a1a

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