Tuesday, October 29, 2019

Joe Sandbox + SIGMA

Is it true that Joe Sandbox supports Sigma? Yes, we have successfully integrated Sigma into Joe Sandbox. Sigma is available in Joe Sandbox Cloud and will be part of the upcoming Joe Sandbox v28 Lapis Lazuli release. 

Do you know what Sigma is? If you don't, this blog post will help you get a better understanding. 

Sigma in a Nutshell

Sigma is a generic and open signature format to detect malware and other security-related events in log files. Which are the log files currently supported? 

  • Firewall logs
  • Operating System logs
  • Proxy logs
  • Web server access logs

For Windows, the operating system logs include:

  • Sysmon events
  • Event logs 
  • Process creation events

Logs are usually kept in a security information and event management system (SIEM). To search in your SIEM or log source, Sigma offers to convert your rule into a search query specific to your SIEM product (the target):

Currently, Sigma rules can be converted to the following targets:

  • Splunk (plain queries and dashboards)
  • ElasticSearch Query Strings
  • ElasticSearch Query DSL
  • Kibana
  • Elastic X-Pack Watcher
  • Logpoint
  • Windows Defender Advanced Threat Protection (WDATP)
  • Azure Sentinel / Azure Log Analytics
  • Sumologic
  • ArcSight
  • QRadar
  • Qualys
  • RSA NetWitness
  • PowerShell
  • Grep

By supporting so many targets, Sigma has a tremendous advantage: one rule can be used in various SIEMs. This allows sharing, prevents vendor lock-in, and makes Sigma generic. 

Sigma and Joe Sandbox

Okay, Sigma is great, but Joe Sandbox is not a SIEM! So how shall Joe Sandbox benefit from Sigma?
Well, Sigma is being used (among other things) to write threat detection rules for events such as Sysmon events, Windows event logs, and operating system process creation events. All those events are captured during the detonation of malware in a sandbox:

If the sandbox understands Sigma, a rule written to detect a threat on the endpoint (e.g. based on Sysmon data) could be also used to detect the threat in the Sandbox. Or the other way around, Sigma rules that were written for a sandbox can be applied to your SIEM! Isn't that fantastic? We truly think it is! 

Sigma in Joe Sandbox enables any customer to write and share threat detection rules based on dynamic data/events even if they don't have a SIEM!

Joe Sandbox also supports Yara rules (including scanning of memory dumps). Yara for the binary world and Sigma for the dynamic world make a perfect combination.


What Sigma rules can I write in Joe Sandbox? Joe Sandbox currently supports eight different events:

  • Process creations (product: windows or linux or macos, category: process_creation)
  • Sysmon: Process creation, Event ID 1 (product: windows, category: sysmon)
  • Sysmon: Network connection, Event ID 3 (product: windows, category: sysmon)
  • Sysmon: Remote thread creation, Event ID 8 (product: windows, category: sysmon)
  • Sysmon: File creation, Event ID 11 (product: windows or linux or macos, category: sysmon)
  • Sysmon: Registry key set, Event ID 13 (product: windows, category: sysmon)
  • Powershell: Powershell Transcript Logging (product: windows, service: powershell)
  • Windows Event Logs (product: windows, service: security|application|system)

A detailed description of the event fields can be found in our user guide under Sigma - List of events.

We have directly added Linux and macOS support for the process creation and file creation event. With that, you can write Sigma rules covering Linux and macOS threats!


Sigma rules are written in YAML format and have a very simple structure. Below you can see an example which uses the process creation event as input:

Joe Sandbox uses various optional meta attributes, such as threatname, behaviorgroup or id. This helps Joe Sandbox to identify threats and do proper classification. The level attribute impacts the verdict of the sandbox. For instance, many Sigma rules matched with a critical level will lead to an overall malicious verdict. 

The heart of the rule is the detection definition which contains a selector with fields or lists. Fields and lists have great wildcard support. The condition is a Boolean expression which in case it evaluates to true, will lead to a rule match.

You can find a full specification of Sigma here

Importing Rules

Importing Sigma rules is super easy. Note you don't need to convert any of the Sigma rules. Joe Sandbox understands Sigma natively. 

To import a rule go to the Editor navigation tab. Then click Sigma:

You might either upload a Sigma rule as a .yml file or a zip of .yml files or alternatively  specify a Github repository containing Sigma rules:

In this case, Joe Sandbox will always import the latest Sigma rule from that repository. Very handy for open source repositories! 

Do you want to modify a rule? This can be easily done in the Sigma editor:

Sigma matches

Once you have imported a rule, you will find the Sigma matches for the new analysis in the full behavior report:

In the top navigation bar click on Overview - Sigma Overview:

Clicking on Show sources will tell you the underlying event responsible for the match:

Sigma Rule Feed

The events supported by Joe Sandbox cover currently around 70% of all community Sigma rules

Joe Security itself started writing its own Sigma rules and decided to share all of the current and new rules with the community under the GPL license. You will find all our Sigma rules on Github: https://github.com/joesecurity/sigma-rules


We have uploaded the current Sigma and Joe Security community rules to Joe Sandbox Cloud Basic. You can easily search matched Sigma rules by using Joe Sandbox View, our threat hunting & search engine:

Via Sigma, Joe Sandbox found a sample using Get2Downloader, likely associated with TA505:

Or here, a Sigma based Wannacry detection via the open-source rules:

Joint Power

Sigma is great, it is generic and therefore allows to easily share threat rules. There is no vendor lock-in. Joe Sandbox's community rules, once converted, can be used to search in many SIEMs. 

You can write your own Sigma rules and use them in Joe Sandbox. Simply upload them in the Sigma editor and you are ready to rock! 

Joe Security has committed to open source all its major Sigma rules on the Joe Security Sigma Github Repo

Would you like to try Joe Sandbox? Then contact us today to get a trial for Joe Sandbox Cloud Pro. 

Wednesday, October 2, 2019

Joe Sandbox 27.0.0 - Red Agate is out!

Over the last couple of months, we have been listening to your feedback and working hard to provide you with the world's most powerful malware analysis system for Windows, macOS, Android, Linux and iOS. Today we release Joe Sandbox 27 under the code name Red Agate! This release is packed with brand new features and improvements, designed to make malware analysis deeper and more precise than ever!

Our Joe Sandbox Cloud ProBasic and OEM servers have already been upgraded to Red Agate recently.

If you wish to upgrade your on-premise Joe Sandbox DesktopMobileXLinuxComplete 

or Ultimate installation right away, please run the following command:

mono joeboxserver.exe --updatefast

Even though we're thrilled about many aspects of this release, in this blog post we will highlight only a few of our favorite Joe Sandbox Red Agate features.

163 new Behavior Signatures

With these brand new signatures, Joe Sandbox is able to precisely detect various malware families like MegaCortex, Dridex, Ryuk, CresentCore, NetWire, Watchbog, Necro and many more.

2986 Community Yara Rules

There is a big number of community Yara rules out there. We took all of them and built a selection by checking them for performance and FPs. The final selection of 2'986 rules has been included in Red Agate and greatly increases detection and malware classification capabilities in Joe Sandbox.

47 Custom Yara rules

Red Agate also includes 47 new custom rules. Those rules are written by Joe Security's threat intelligence analysts and extend the community rules:

Web Push Notifications

The Web Interface now features Push Notifications. Push notifications are very useful in notifying end-users as soon as an analysis is finished or an analyzer is ready for remote assistance:

Joe Sandbox will ask you to enable Push Notifications once during submission, and you can also enable or disable it later on in your user settings. 

Threat Names

Threat Names have been added in order to easily identify which threat has been detected by Joe Sandbox. Threat Names are shown in the analysis overview page as well as inside the report:

Intelligent Analysis

Particular samples often require command-line arguments properly execute and show malicious behavior. Others need to be run as part of a service. For these specific cases, Joe Sandbox will automatically re-analyze the sample with the right action, tremendously increasing the execution success.

Joe Sandbox Detect

Joe Sandbox Detect is a powerful endpoint client which detects suspicious files delivered via targeted attacks or spear-phishing campaigns. It directly leverages the power of Joe Sandbox Red Agate.

If you want to learn more about Joe Sandbox Detect please have a look at this blog post.

Final Words

In this blog post, we have presented the most important features of Joe Sandbox Red Agate, but there are some other very interesting features on top:

Would you like to try Joe Sandbox? Register for a free account on Joe Sandbox Cloud Basic or contact us for an in-depth technical demo!

Tuesday, September 3, 2019

Joe Sandbox + Carbon Black

We are happy to release today the Joe Sandbox - Carbon Black connector! With the connector, Carbon Black Response users benefit from automated deep malware analysis with Joe Sandbox. The connector will submit suspicious files detected by Carbon Black to Joe Sandbox for deeper analysis and will import the generated threat intelligence data into Carbon Black.

You find our Carbon Black connector as well as the installation guide in our Github repository: https://github.com/joesecurity/carbonblack-connector.

Deep Threat Intelligence

Once you have completed the installation you can search for malicious detections via the Binary Search. Click on Add Criteria and then select Joe Sandbox Score:

The Joe Sandbox Score is an indicator of how the behavior has been rated by Joe Sandbox. 0 means no malicious behavior while 100 is very malicious. In the new form, you can define if you would like to search for all binaries with e.g. a Joe Sandbox Score higher or equal than X:

A score bigger or equal to 50 means the sample shows malicious behavior. For our current example Carbon Black found a binary with a score higher or equal than 50 on one endpoint:

Clicking on the hash link provides us with more information on the binary:

We have the Joe Sandbox Score of 100 at the top right. Via the View on joesandbox link we can open up the analysis report:

Since we know now that this is Agent Tesla we can easily block the binary thanks to Carbon Black on all our endpoints with a single click:


Wouldn't it be nice to automatically be alerted as soon as Carbon Black detects a new binary on the endpoint and Joe Sandbox detects it as malicious? This you can achieve by creating a Watchlist. To create one, open Watchlists on the main menu and then use the query "cb.q.alliance_score_joesandbox=[50 TO *]":

Finally, select how you would like to get alerted. 

Joe Sandbox and Carbon Black - a powerful combination

Thanks to the Joe Sandbox Carbon Black connector, cyber security analysts using Carbon Black benefit from deep malware analysis done by Joe Sandbox. This enables to detect and block zero-day and targeted attacks.

Do you want to try Joe Sandbox and use the Joe Sandbox Carbon Black connector? Request a free Joe Sandbox Cloud Pro trial now!

Tuesday, August 20, 2019

Joe Sandbox Detect - the Cloud backed Endpoint Sensor

Today, we are proud to show-case Joe Sandbox Detect. In a nutshell, Joe Sandbox Detect is a configurable endpoint sensor with Joe Sandbox Cloud as its backend. What is an endpoint sensor and why does my organization need it? This blog post addresses those questions.

Endpoint Overloading

Detecting malware on endpoints is a hard job. Endpoint security vendors have to make sure not to consume too many resources, not to interrupt end-users, do not weaken the security and not do conflict with other endpoint security tools. This, of course, limits the effectiveness of malware detection. 

Holy Cloud

The best solution to escape those limitations is to move the malware detection to the Cloud. As a result, the agent is light-weight, with very little resource consumption, high security, and compatibility. The malware detection in the Cloud has access to massive computing resources and will not slow down the endpoint. This design increases the effectiveness of malware detection massively.

Joe Sandbox Detect is a slim endpoint sensor which utilizes Joe Sandbox Cloud for malware detection. Joe Sandbox is the industries deepest malware analysis engine. It uses a combination of static and dynamic malware analysis (sandboxing) to detect even the most sophisticated malware.

Malware Entry Points

Deep malware analysis is great but it also takes time to analyze a file in depth. Thus, it is not possible to analyze any files on an endpoint. To address this challenge Joe Sandbox Detect includes configurable filters. By default, those filters select only files which might contain code and are created by applications which are known for malware entry points (e-mail clients, web browsers, etc).

Filters can be set during installation via command-line arguments.

Notifications and Alerts

Let us assume a user has opened a potential malicious Microsoft Word document via Thunderbird or Outlook:

Joe Sandbox Detect is monitoring e-mail clients for the creation of Microsoft Office documents. Therefore Ferreria's Quote.doc is uploaded for deep inspection to Joe Sandbox Cloud. Joe Sandbox Cloud analyzes the file and once completed will first alert the security team. Joe Sandbox Cloud includes configurable filters for alerts. For instance, the security team can enable that only for malicious detections an alert is sent or only for certain file types:

The security team can also access the analysis data including IOCs and see from which endpoint and application the file origins:

IOCs can be used to block malware on endpoints and search other endpoints for existing infections. Detailed behavior information enables to understand if the threat has spyware, spreading or ransomware functionality. 

After alerting the security team the end-user is also notified. This notification is configurable and can also be disabled. End-users can also open the management report which contains only high-level information:

Privacy - Encrypted Analysis

Because Joe Sandbox Detect might also analyze documents which contain confidential information privacy is extremely important. We recently outlined in a blog post what privacy features Joe Sandbox Cloud implements. Encrypted Analysis is one of these features which also Joe Sandbox Detect uses. Whenever Joe Sandbox Detect uploads a file and the analysis is completed Joe Sandbox Cloud encrypts all data including the file, IOCs, reports, etc. with a random password. Encrypted analyses are indicated with the small lock icon:

The password for encryption is only kept on the end-point. Therefore, Joe Security cannot access the analysis data anymore. Security teams can decide to use a unique password for encryption for all their endpoints during the installation of Joe Sandbox Detect. End-users can also copy the password and share it with the security team on purpose:

Encrypted analyses provide the strongest privacy and are a unique feature of Joe Sandbox Cloud. You don't trust cloud services at all? Joe Security also offers on-premise products which work with Joe Sandbox Detect as good as with Joe Sandbox Cloud.

Manual Submissions

Automated analysis is great but there is also the use case where an end-user detects a malicious e-mail and is not opening the attachments and he still wants to check if he is right. To address this Joe Sandbox Detect includes an optional small bar which shows up on the Desktop. End-users can drag and drop e-mails to this bar for analysis by Joe Sandbox Detect:

This also works for files on USB sticks. The same alerts and notifications are sent as if it were an automated analysis. Analyses are also encrypted. 

Enhancing your Endpoint Security

Joe Sandbox Detect is a unique endpoint sensor with the following feature set:

  • Leverages Joe Sandbox Cloud for in-depth malware analysis
  • Configurable filters to define what is analyzed and what not
  • Extensive alerting for SOCs
  • Complete privacy due to encrypted analyses
  • Extremely low resource consumption
  • Compatible with any other endpoint security solution
  • Convenient manual submissions
  • Parameterized MSI installer for easy deployment

Want to try Joe Sandbox Detect and test its malware detection capabilities? Contact us today for a trial or an in-depth technical demo!