Category Archives: Malware

Ensuring Cybersecurity: Blocking Discord Access with Firewall Rules

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I. Introduction

Purpose of Blocking Discord Access

Social media and communication platforms like Discord are everywhere in today’s digital landscape. However, their widespread use also introduces significant cybersecurity risks. Discord, known for its extensive user base and real-time communication features, can be a vector for malicious actors’ malware distribution and command and control (C2) operations. Blocking access to Discord within a corporate environment is a proactive measure to mitigate these risks.

Importance of Controlled Access to Prevent Malware Command and Control

Controlling access to external platforms is crucial in preventing unauthorized use of corporate resources for malicious purposes. By restricting access to platforms like Discord, organizations can reduce the risk of malware infections, data breaches, and unauthorized communications. This measure helps keep network integrity and security intact, safeguarding sensitive business information from cyber threats.

II. Assessing Business Needs

Identifying Users with Legitimate Business Needs

Before implementing a blanket ban on Discord, it’s essential to identify any legitimate business needs for accessing the platform. This could include marketing teams monitoring brand presence, developers collaborating with external partners, or customer support teams engaging with clients through Discord channels.

Documenting and Justifying Business Needs

Once legitimate needs are identified, they should be documented comprehensively. This documentation should include the specific reasons for access, the potential benefits to the business, and any risks associated with allowing such access. This step ensures that decisions are transparent and justifiable.

Approval Process for Access

Establish a formal approval process for users requesting access to Discord. This process should involve a thorough IT and security team review, considering the documented business needs and potential security risks. Approved users should be granted access through secure, monitored channels to ensure compliance with corporate policies.

III. Technical Controls

A. Network Segmentation

Isolating Critical Systems

One of the fundamental strategies in cybersecurity is network segmentation. Organizations can limit the potential impact of a security breach by isolating critical systems from the rest of the network. Critical systems should be placed in separate VLANs (Virtual Local Area Networks) with strict access controls.

Implementing VLANs

Creating VLANs for different departments or user groups can help manage and monitor network traffic more effectively. For instance, placing high-risk users (those needing access to external platforms like Discord) in a separate VLAN allows for focused monitoring and control without impacting the broader network.

B. Firewall Rules

Blocking Discord-Related IPs and Domains

To block Discord access, configure firewall rules to block known Discord IP addresses and domain names. For example:

! Block Discord IP addresses
access-list 101 deny ip any host 162.159.129.233
access-list 101 deny ip any host 162.159.128.233

! Block Discord domain names
ip domain list discord.com
ip domain list discord.gg
access-list 101 deny ip any host discord.com
access-list 101 deny ip any host discord.gg

! Apply the access list to the appropriate interface
interface GigabitEthernet0/1
 ip access-group 101 in

For comprehensive lists of Discord servers and IPs to block, refer to resources such as:

Creating Whitelists for Approved Users

For users with approved access, create specific firewall rules to allow traffic. This can be done by setting up a whitelist:

! Allow approved users to access Discord
access-list 102 permit ip host approved_user_ip any

! Apply the whitelist access list to the appropriate interface
interface GigabitEthernet0/1
 ip access-group 102 in

C. Proxy Servers

Filtering Traffic

Utilize proxy servers to filter and control web traffic. Proxy servers can block access to Discord by filtering requests to known Discord domains. This ensures that only approved traffic passes through the network.

Monitoring and Logging Access

Proxy servers should also be configured to monitor and log all access attempts. These logs should be reviewed regularly to detect unauthorized access attempts and potential security threats.

D. Application Control

Blocking Discord Application

Application control can prevent the installation and execution of the Discord application on corporate devices. Use endpoint security solutions to enforce policies that block unauthorized software.

Allowing Access Only to Approved Instances

For users who need Discord for legitimate reasons, ensure they use only approved instances. This can be managed by allowing access only through specific devices or within certain network segments, with continuous monitoring for compliance.

Conclusion

Blocking Discord access in a corporate environment involves a multi-layered approach combining policy enforcement, network segmentation, firewall rules, proxy filtering, and application control. Organizations can mitigate the risks associated with Discord by thoroughly assessing business needs, documenting justifications, and implementing robust technical controls while allowing necessary business functions to continue securely.

For assistance or additional insights on implementing these controls, contact MicroSolved. Our team of experts is here to help you navigate the complexities of cybersecurity and ensure your organization remains protected against emerging threats.

 

 

* AI tools were used as a research assistant for this content.

 

How to Craft Effective Prompts for Threat Detection and Log Analysis

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Introduction

As cybersecurity professionals, log analysis is one of our most powerful tools in the fight against threats. By sifting through the vast troves of data generated by our systems, we can uncover the telltale signs of malicious activity. But with so much information to process, where do we even begin?

The key is to arm ourselves with well-crafted prompts that guide our investigations and help us zero in on the threats that matter most. In this post, we’ll explore three sample prompts you can use to supercharge your threat detection and log analysis efforts. So grab your magnifying glass, and let’s dive in!

Prompt 1: Detecting Unusual Login Activity

One common indicator of potential compromise is unusual login activity. Attackers frequently attempt to brute force their way into accounts or use stolen credentials. To spot this, try a prompt like:

Show me all failed login attempts from IP addresses that have not previously authenticated successfully to this system within the past 30 days. Include the source IP, account name, and timestamp.

This will bubble up login attempts coming from new and unfamiliar locations, which could represent an attacker trying to gain a foothold. You can further refine this by looking for excessive failed attempts to a single account or many failed attempts across numerous accounts from the same IP.

Prompt 2: Identifying Suspicious Process Execution

Attackers will often attempt to run malicious tools or scripts after compromising a system. You can find evidence of this by analyzing process execution logs with a prompt such as:

Show me all processes launched from temporary directories or user profile AppData directories. Include the process name, associated username, full command line, and timestamp.

Legitimate programs rarely run from these locations, so this can quickly spotlight suspicious activity. Pay special attention to scripting engines like PowerShell or command line utilities like PsExec being launched from unusual paths. Examine the full command line to understand what the process was attempting to do.

Prompt 3: Spotting Anomalous Network Traffic

Compromised systems frequently communicate with external command and control (C2) servers to receive instructions or exfiltrate data. To detect this, try running the following prompt against network connection logs:

Show me all outbound network connections to IP addresses outside of our organization’s controlled address space. Exclude known good IPs like software update servers. Include source and destination IPs, destination port, connection duration, and total bytes transferred.

Look for long-duration connections or large data transfers to previously unseen IP addresses, especially on non-standard ports. Correlating this with the associated process can help determine if the traffic is malicious or benign.

Conclusion

Effective prompts like these are the key to unlocking the full potential of your log data for threat detection. You can quickly identify the needle in the haystack by thoughtfully constructing queries that target common attack behaviors.

But this is just the beginning. As you dig into your findings, let each answer guide you to the next question. Pivot from one data point to the next to paint a complete picture and scope the full extent of any potential compromise.

Mastering the art of prompt crafting takes practice, but the effort pays dividends. Over time, you’ll develop a robust library of questions that can be reused and adapted to fit evolving needs. So stay curious, keep honing your skills, and happy hunting!

More Help?

Ready to take your threat detection and log analysis skills to the next level? The experts at MicroSolved are here to help. With decades of experience on the front lines of cybersecurity, we can work with you to develop custom prompts tailored to your unique environment and risk profile. We’ll also show you how to integrate these prompts into a comprehensive threat-hunting program that proactively identifies and mitigates risks before they impact your business. Be sure to start asking the right questions before an attack succeeds. Contact us today at info@microsolved.com to schedule a consultation and build your defenses for tomorrow’s threats.

 

* AI tools were used as a research assistant for this content.

 

Saved By Ransomware Presentation Now Available

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I recently spoke at ISSA Charlotte, and had a great crowd via Zoom. 

Here is the presentation deck and MP3 of the event. In it, I shared a story about an incident I worked around the start of Covid, where a client was literally saved from significant data breach and lateral spread from a simple compromise. What saved them, you might ask? Ransomware. 

That’s right. In this case, ransomware rescued the customer organization from significant damage and a potential loss of human life. 

Check out the story. I think you’ll find it very interesting. 

Let me know if you have questions – hit me up the social networks as @lbhuston.

Thanks for reading and listening! 

Deck: https://media.microsolved.com/SavedByRansomware.pdf

MP3: https://media.microsolved.com/SavedByRansomware.mp3

PS – I miss telling you folks stories, in person, so I hope you enjoy this virtual format as much as I did creating it! 

That phone call you dread…

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So, you’re a sysadmin, and you get a call from that friend and co-worker…we all know that our buddies don’t call the helpdesk, right?

This person sheepishly admits that they got an email that looked maybe a bit suspicious in hindsight, it had an attachment…and they clicked.

Yikes. Now what?

Well, since you’re an EXCELLENT sysadmin, and you work for the best company ever, you’ve done a few things to make sure you’re ready for this day…

  • The company has had a business impact analysis, so all of the relevant policies and procedures are in place.
  • Your backups are in place, offsite, and you know you can restore them with a modicum of effort – and because you’ve done baselines, you know how long it will take to restore.
  • Your team has been doing incident response tabletops, so all of the IR processes are documented and up-to-date. And you set it up to be a good time, so they were fully engaged in the process.

But now, one of your people has clicked…now what, indeed..

  • Pull. The. Plug. Disconnect that system. If it’s hard wired, yank the cord. If it’s on a wifi network, kick it off – take down the whole wifi network if feasible. The productivity that you’ll lose will be outweighed by the gains if you can stop lateral spread of the infection.
  • Pull any devices – external hard drives, USB sticks, etc.
  • DO NOT power the system off – not yet! If you need to do forensics, the live system memory will be important.

Now you can breathe, but just for a minute. This is the time to act with strategy as well as haste. Establish whether you’ve got a virus or ransomware infection, or if the ill-advised click was an attachment of another nature.

If it’s spam, but not malicious:

  • Check the email information in your email administration portal, and see if it was delivered to other users. Notify them as necessary.
  • Evaluate key features of the email – are there changes you should make to your blocking and filtering? Start that process.
  • Parse and evaluate the email headers for IPs and/or domains that should be blocked. See if there are indicators of other emails with these parameters that were blocked or delivered.
  • Add the scenario of this email to your user education program for future educational use.

If it’s a real infection, full forensics is beyond the scope of this blog post. But we’ll give a few pointers to get you started.

If it’s a virus, but not ransomware:

  • If the file that was delivered is still accessible, use VirusTotal and other sites to see if it’s known to be malicious. The hash can be checked, as well as the file itself.
  • Consider a full wipe of the affected system, as opposed to a virus removal – unless you’re 100% successful with removal, repeated infection is likely.
  • All drives or devices – network, USB, etc. – that were connected to the system should be suspect. Discard those you can, clean network drives or restore from backup.
  • Evaluate the end user account – did the attacker have time to elevate privileges? Check for any newly created accounts, as well.
  • Check system and firewall logs for traffic to and from the affected system, as well as any ancillary systems.

If it’s ransomware:

  • Determine what kind of ransomware you are dealing with.
  • Determine the scope of the infection – ancillary devices, network shares, etc.
  • Check to see if a decrypt tool is available – be aware these are not always successful.
  • Paying the ransom, or not, is a business decision – often the ransom payments are not successful, and the files remain encrypted. Address this in your IR plan, so the company policy is defined ahead of time.
  • Restore files from backup.
  • Strongly consider a full wipe of the system, even if the files are decrypted.
  • Evaluate the end user account – did the attacker have time to elevate privileges? Check for any newly created accounts, as well.
  • Check system and firewall logs for traffic to and from the affected system, as well as any ancillary systems.

In all cases, go back and map the attack vector. How did the suspect attachment get in, and how can you prevent it going forward?

What are your thoughts? I’d love to hear from you – lwallace@microsolved.com, or @TheTokenFemale on Twitter!

You backed it up, right?

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Yes, folks…we’re back to basics here. Anyone think we’d still be talking about this in 2018? We are…

Our recent incident response work has brought this to the front of my mind. Think for just a minute about a company who has a business vs. technology conflict. They want their backups to be QUICK! So they put their backups on a NAS. Network attached storage.

Key word there – attached. Now, let’s role play that they have been hit by ransomware. They can restore their backups quickly…and now they’ve lost their backups quickly as well. How catastrophic would this be for you?

There are several things to think about when it comes to your backup strategy. First, what do you need to protect against?

  • Natural disasters. Onsite backups are convenient, but not terribly convenient if your whole building burns down. Are you in an earthquake zone? Tornadoes? Hurricanes?What kind of catastrophic happenings could you experience, and how far away do your backups have to be to be protected?
  • Risk from external attackers. Going back to our ransomeware scenario above, what’s the balance between ease of restoring backups vs. protection from harm for your organization?
  • Risk from internal attackers. We all want to trust our sysadmins. What happens if one of them is disgruntled? What safeguards are in place to protect your backups from internal threats?
  • Testing your backups. Periodically perform testing of your backups, both inside and outside of an incident response tabletop. Make sure that your backed up data really IS backed up, and restores in the manner you’d expect. This is a good time to create some baselines on the restore process, as well – what’s your time to restoration if a crisis happens?
  • Hot vs. cold disaster recovery systems. How critical is downtime to your business? If hours means millions, you should have – or seriously consider – a “hot” disaster recovery site to minimize downtime as you pivot over.

Backups are routine, and boring…and when things go well, they should be this way. Prepare yourself for the day things do NOT go well, eh?

What do you think? I’d love to hear what I’ve forgotten – reach out to lwallace@microsolved.com or @TheTokenFemale on Twitter.

Ransomware TableTop Exercises

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When it comes to Ransomware, it’s generally a good idea to have some contingency and planning before your organization is faced with a real life issue. Here at MicroSolved we offer tabletop exercises tailored to this growing epidemic in information technology. 

 

What if your organization was affected by the Golden Eye or WannaCry today? How quick would you be able to react? Is someone looking at your router or server log files? Is this person clearly defined? How about separation of duties? Is the person looking over the log files also uncharge of escalating an issue to higher management?

 

How long would it take for you organization to even know if it was affected? Who would be in-charge of quarantining the systems? Are you doing frequent backups? Would you bet your documents on it? To answer these questions and a whole lot more it would be beneficial to do a table top exercise. 

 

A table top exercise should be implemented on an annual basis to evaluate organizational cyber incident prevention, mitigation, detection and response readiness, resources and strategies form the organizations respective Incident Response Team. 

 

As you approach an incident response there are a few things to keep in mind:

 

  1. Threat Intelligence and Preparation

An active threat intelligence will help your organization to Analyze, Organize and refine information about potential attacks that could threaten the organization as a whole.

After you gain Threat Intelligence, then there needs to be a contingency plan in place for what to do incase of an incident. Because threats are constantly changing this document shouldn’t be concrete, but more a living document, that can change with active threats.

  1. Detection and Alerting

The IT personal that are in place for Detection and Alerting should be clearly defined in this contingency plan. What is your organizations policy and procedure for frequency that the IT pro’s look at log files, network traffic for any kind of intrusion?

  1. Response and Continuity

When an intrusion is identified, who is responsible for responding? This response team should be different then the team that is in charge of “Detection and Alerting”. Your organization should make a clearly outlined plan that handles response. The worse thing is finding out you don’t do frequent backups of your data, when you need those backups! 

  1. Restoring Trust

After the incident is over, how are you going to gain the trust of your customers? How would they know there data was safe/ is safe? There should be a clearly defined policy that would help to mitigate any doubt to your consumers. 

  1. After Action Review

What went wrong? Murphy’s law states that when something can go wrong it will. What was the major obstacles? How can this be prevented in the future? This would be a great time to take lessons learned and place them into the contingency plan for future. The best way to lesson the impact of Murphy, is to figure out you have an issue on a table top exercise, then in a real life emergency! 


This post was written by Jeffrey McClure.

Petya/PetyaWrap Threat Info

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As we speak, there is a global ransomware outbreak spreading. The infosec community is working together, in the open, on Twitter and mailing lists sharing information with each other and the world about the threat. 

The infector is called “Petya”/“PetyaWrap” and it appears to use psexec to execute the EternalBlue exploits from the NSA.

The current infector has the following list of target file extensions in the current (as of an hour ago) release. https://twitter.com/bry_campbell/status/879702644394270720/photo/1

Those with robust networks will likely find containment a usual activity, while those who haven’t implement defense in depth and a holistic enclaving strategy are likely in trouble.

Here are the exploits it is using: CVE-2017-0199 and MS17-010, so make sure you have these patched on all systems. Make sure you find anything that is outside the usual patch cycle, like HVAC, elevators, network cameras, ATMs, IoT devices, printers and copiers, ICS components, etc. Note that this a combination of a client-side attack and a network attack, so likely very capable of spreading to internal systems… Client side likely to yield access to internals pretty easily.

May only be affecting the MBR, so check that to see if it is true for you. Some chatter about multiple variants. If you can open a command prompt, bootrec may help. Booting from a CD/USB or using a drive rescue tool may be of use. Restore/rebuild the MBR seems to be successful for some victims. >>  “bootrec /RebuildBcd bootrec /fixMbr bootrec /fixboot” (untested)

New Petrwrap/Petya ransomware has a fake Microsoft digital signature appended. Copied from Sysinternals Utils. – https://t.co/JooBu8lb9e

Lastline indicated this hash as an IOC: 027cc450ef5f8c5f653329641ec1fed91f694e0d229928963b30f6b0d7d3a745 – They also found these activities: https://pbs.twimg.com/media/DDVj-llVYAAHqk4.jpg

Eternal Blue detection rules are firing in several detection products, ET Rules firing on that Petya 71b6a493388e7d0b40c83ce903bc6b04  (drops 7e37ab34ecdcc3e77e24522ddfd4852d ) – https://twitter.com/kafeine/status/879711519038210048

Make sure Office updates are applied, in addition to OS updates for Windows. <<Office updates needed to be immune to CVE-2017-0199.

Now is a great time to ensure you have backups that work for critical systems and that your restore processes are functional.

Chatter about wide scale spread to POS systems across europe. Many industries impacted so far.

Bitdefender initial analysis – https://labs.bitdefender.com/2017/06/massive-goldeneye-ransomware-campaign-slams-worldwide-users/?utm_source=SMGlobal&utm_medium=Twitter&utm_campaign=labs

Stay safe out there! 

 

—

3:48pm Eastern

Update: Lots of great info on detection, response, spread and prevention can be found here: https://securelist.com/schroedingers-petya/78870/

Also, this is the last update to this post unless something significant changes. Follow me on Twitter for more info: @lbhuston 

Quick Look at Ransomware Content

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Ransomware certainly is a hot topic in information security these days. I thought I would take a few moments and look at some of the content out there about it. Here are some quick and semi-random thoughts on the what I saw.

  • It very difficult to find an article on ransomware that scores higher than 55% on objectivity. Lots of marketing going on out there.
  • I used the new “Teardown” rapid learning tool I built to analyze 50 of the highest ranked articles on ransomware. Most of that content is marketing, even from vendors not associated with information security or security in general. Lots of product and service suggestive selling going on…
  • Most common tip? Have good and frequent backups. It helps if you make sure they restore properly.
  • Most effective tip, IMHO? Have strong egress controls. It helps if you have detective controls and process that are functional & effective.
  • Worst ransomware tip from the sample? Use a registry hack across all Windows machines to prevent VBS execution. PS – Things might break…

Overall, it is clear that tons of vendors are using ransomware and WannaCry as a marketing bandwagon. That should make you very suspicious of things you read, especially those that seem vendor or product specific. If you need a set of good information to use to present ransomware to your board or management team, I thought the Wikipedia article here was pretty decent information. Pay attention to where you get your information from, and until next time, stay safe out there!

Introducing AirWasp from MSI!

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For over a decade, HoneyPoint has been proving that passive detection works like a charm. Our users have successfully identified millions of scans, probes and malware infections by simply putting “fake stuff” in their networks, industrial control environments and other strategic locations. 

 

Attackers have taken the bait too; giving HoneyPoint users rapid detection of malicious activity AND the threat intelligence they need to shut down the attacker and isolate them from other network assets.

 

HoneyPoint users have been asking us about manageable ways to detect and monitor for new WiFi networks and we’ve come up with a solution. They wanted something distributed and effective, yet easy to use and affordable. They wanted a tool that would follow the same high signal, low noise detection approach that they brag about from their HoneyPoint deployments. That’s exactly what AirWasp does.

 

We created AirWasp to answer these WiFi detection needs. AirWasp scans for and profiles WiFi access points from affordable deck-of-cards-sized appliances. It alerts on any detected access points through the same HoneyPoint Console in use today, minimizing new cost and management overhead. It also includes traditional HoneyPoints on the same hardware to help secure the wired network too!

 

Plus, our self-tuning white list approach means you are only alerted once a new access point is detected – virtually eliminating the noise of ongoing monitoring. 

 

Just drop the appliance into your network and forget about it. It’ll be silent, passive and vigilant until the day comes when it has something urgent for you to act upon. No noise, just detection when you need it most.

 

Use Cases:

 

  • Monitor multiple remote sites and even employee home networks for new Wifi access points, especially those configured to trick users
  • Inventory site WiFi footprints from a central location by rotating the appliance between sites periodically
  • Detect scans, probes and worms targeting your systems using our acclaimed HoneyPoint detection and black hole techniques
  • Eliminate monitoring hassles with our integration capabilities to open tickets, send data to the SIEM, disable switch ports or blacklist hosts using your existing enterprise products and workflows

More Information

 

To learn how to bring the power and flexibility of HoneyPoint and AirWasp to your network, simply contact us via email (info@microsolved.com) or phone (614) 351-1237.


 

We can’t wait to help you protect your network, data and users!


State of Security Podcast Episode 11 is Out!

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“Hey, I heard you missed us. We’re back! … I brought my pencil, give me something to write on, man!” — Van Halen

That’s right – we heard you and we’re back. It took 7 months to rework the podcast format, find a new audio post processor to partner with, close the deal, do some work on the Honorary Michael Radigan Studios and bring the whole thing back to you in a new audio package. Whew! 🙂 

That said, check out the new episode of the podcast as Lisa Wallace tears into malware history, discusses why she loves infosec and gives some advice to women working in the industry. There’s a lot of great stuff here, packed into ~40 minutes.

Look for new episodes coming soon, and hopefully with an increased pace. Hit me up on Twitter and let me know what you think! (@lbhuston). Enjoy the audio goodness and thanks for listening!