Accelerate your SSE journey. Join Netskope at RSA.

  • Security Service Edge Products

    Protect against advanced and cloud-enabled threats and safeguard data across all vectors.

  • Borderless SD-WAN

    Confidently provide secure, high-performance access to every remote user, device, site, and cloud.

  • Platform

    Unrivaled visibility and real-time data and threat protection on the world's largest security private cloud.

Netskope Named a Leader in the 2022 Gartner Magic Quadrant™ for SSE Report

Get the report Go to Products Overview
Netskope gartner mq 2022 sse leader
Gartner® Quick Answer: How Does Netskope’s Acquisition of Infiot Impact SD-WAN, SASE, and SSE Projects?

Get the report
Gartner quick answer
Netskope delivers a modern cloud security stack, with unified capabilities for data and threat protection, plus secure private access.

Explore our platform
Birds eye view metropolitan city
Make the move to market-leading cloud security services with minimal latency and high reliability.

Learn more
Lighted highway through mountainside switchbacks
Prevent threats that often evade other security solutions using a single-pass SSE framework.

Learn more
Lighting storm over metropolitan area
Zero trust solutions for SSE and SASE deployments

Learn more
Boat driving through open sea
Netskope enables a safe, cloud-smart, and fast journey to adopt cloud services, apps, and public cloud infrastructure.

Learn more
Wind turbines along cliffside
  • Our Customers

    Netskope serves more than 2,000 customers worldwide including more than 25 of the Fortune 100

  • Customer Solutions

    We are here for you and with you every step of the way, ensuring your success with Netskope.

  • Training and Certification

    Netskope training will help you become a cloud security expert.

We help our customers to be Ready for Anything

See our Customers
Woman smiling with glasses looking out window
Netskope’s talented and experienced Professional Services team provides a prescriptive approach to your successful implementation.

Learn more
Netskope Professional Services
Secure your digital transformation journey and make the most of your cloud, web, and private applications with Netskope training.

Learn more
Group of young professionals working
  • Resources

    Learn more about how Netskope can help you secure your journey to the cloud.

  • Blog

    Learn how Netskope enables security and networking transformation through security service edge (SSE).

  • Events & Workshops

    Stay ahead of the latest security trends and connect with your peers.

  • Security Defined

    Everything you need to know in our cybersecurity encyclopedia.

Security Visionaries Podcast

Episode 10: Building Security Relationships Through Transparency
In this episode, Mike and Andreas discuss aligning with works councils, forging business relationships through transparency, and embedding security into value streams.

Play the podcast
Building Security Relationships Through Transparency
Read the latest on how Netskope can enable the Zero Trust and SASE journey through security service edge (SSE) capabilities.

Read the blog
Sunrise and cloudy sky
Netskope at RSA

Join Netskope at RSA Conference this year and be part of the real conversations on SASE and Zero Trust. Stop by our booth in South Hall, chat with an expert, register for our speaking sessions, and unwind by joining us at one of our events!

Learn more
RSA logo
What is Security Service Edge?

Explore the security side of SASE, the future of network and protection in the cloud.

Learn more
Four-way roundabout
  • Company

    We help you stay ahead of cloud, data, and network security challenges.

  • Why Netskope

    Cloud transformation and work from anywhere have changed how security needs to work.

  • Leadership

    Our leadership team is fiercely committed to doing everything it takes to make our customers successful.

  • Partners

    We partner with security leaders to help you secure your journey to the cloud.

Netskope enables the future of work.

Find out more
Curvy road through wooded area
Netskope is redefining cloud, data, and network security to help organizations apply Zero Trust principles to protect data.

Learn more
Switchback road atop a cliffside
Thinkers, builders, dreamers, innovators. Together, we deliver cutting-edge cloud security solutions to help our customers protect their data and people.

Meet our team
Group of hikers scaling a snowy mountain
Netskope’s partner-centric go-to-market strategy enables our partners to maximize their growth and profitability while transforming enterprise security.

Learn more
Group of diverse young professionals smiling

Resurgence of Locky Ransomware with LUKITUS extension

Aug 18 2017
Vulnerability Advisory

Update August 31, 2017: Netskope Threat Research Labs has spotted that Locky variant LUKITUS now using 7Z format for email attachments. It uses simple names for attachment like documents.7z, photos.7z, scans.7z. The attachment contains malicious VBS script code which downloads Locky Ransomware and encrypts user files with “.LUKITUS” extensions as detailed in our recent blog. Netskope Threat Protection detects the VBS archived in the 7zip as “vb:trojan.agnt.cmbk” and the payload as “Win32:Trojan:Locky:L”.

Last year, Netskope Threat Research Labs blogged about various evolution stages of the popular Locky Ransomware namely usage of cloud apps, usage of DLL (Dynamic Link Library) instead of EXE (Executable File) and usage of “.AESIR” and “.ZZZZZ” extensions for encrypted files.  Netskope Threat Research Labs has constantly been tracking campaigns related to Locky, which after remaining passive in last couple months has emerged with a massive ongoing email campaign. The emails are sent with zip file as an attachment. The zip file contains malicious VBScript or JavaScript which act as downloader for Locky variant Ransomware. The Ransomware on execution encrypts the files using a new extension “.LUKITUS”. Netskope Threat Protection detects the malicious VBS and JS files as Backdoor.js.ryw and Backdoor.JS.agnt.qvs respectively. The blog provides more details about the workings of the malware.

Analysis of VBScript and JavaScript files

As mentioned earlier, this variant of Locky spreads either via VBScript or JavaScript file bundled inside ZIP archives as attachments. Both format of the scripts are obfuscated. For example of one of the malicious VBScript code we analyzed is shown in Figure 1.

Figure 1: Malicious VBScript code

On the same lines, an example of one of the JavaScript code we analyzed is shown in Figure 2.

Figure 2: Malicious JavaScript code

These scripts act as downloaders, which on execution download and execute the LUKITUS variant of the ransomware. The script contains array of URLs to download malicious payload as shown in Figure 3.

Figure 3: List of URLs to download malicious payloads.

The malicious payload is downloaded from compromised domains as shown in Figure 4.

Figure 4: Malicious payload is downloaded from compromised domains.

The downloaded payload is saved under %TEMP% directory with random names. Both scripts download different payloads from compromised domains but the mechanism of downloading the LUKITUS variant payload is same. The details of the payloads downloaded by the scripts at the time of analysis are as listed below

VBS payload MD5: 3D4E88B3BA4D128BB171B74B1F6F641A

Netskope detection:Backdoor.ransm.cerbrkd.12157876

JS payload MD5: AE2E796443D66A9838E2EF9418C66F20

Netskope detection: Backdoor.generckd.5841337

The payload then uploads system information to its C&C server using HTTP POST request as shown in Figure 5.

Figure 5: C&C communication over HTTP POST request.

The payload then encrypts files with LUKITUS extension as shown in Figure 6.

Figure 6: Files are encrypted with LUKITUS extensions

Once it finishes the encryption of files, it will display a ransom warning as shown in Figure 7.

Figure 7: LUKITUS ransom warning message.


Locky ransomware continues to be in the limelight using different variants since its inception. We have seen a huge spike in LUKITUS variants in last couple of days. Although, there is no major change apart from the new extension for encrypted files, the spike in campaign suggests that the threat actors behind the campaign are still using Locky Ransomware to spread and infect systems.Since the variants have a similar infection mechanism with only a change in extensions for encrypted files, we potentially suspect the use of a Locky payload builder toolkit. Netskope Threat Research Labs is continuously monitoring the evolution of ransomware strains, including Locky, and will report the use of any new techniques and evasions.

General Recommendations

Netskope recommends the following to combat cloud malware and threats:

  • Detect and remediate cloud threats using a threat-aware CASB solution like Netskope and enforce policy on usage of unsanctioned services as well as unsanctioned instances of sanctioned cloud services
  • Sample policies to enforce:
    • Scan all uploads from unmanaged devices to sanctioned cloud services for malware
    • Scan all uploads from remote devices to sanctioned cloud  services for malware
    • Scan all downloads from unsanctioned cloud  services for malware
    • Scan all downloads from unsanctioned instances of sanctioned cloud  services for malware
    • Enforce quarantine/block actions on malware detection to reduce user impact
    • Block unsanctioned instances of sanctioned/well known cloud  services, to prevent attackers from exploiting user trust in cloud. While this seems a little restrictive, it significantly reduces the risk of malware infiltration attempts via cloud
  • Enforce DLP policies to control files and data en route to or from your corporate environment
  • Regularly back up and turn on versioning for critical content in cloud services
  • Enable the “View known file extensions” option on Windows machines
  • Warn users to avoid executing unsigned macros and macros from an untrusted source, unless they are very sure that they are benign
  • Warn users to avoid executing any file unless they are very sure that they are benign
  • Warn users against opening untrusted attachments, regardless of their extensions or filenames
  • Keep systems and antivirus updated with the latest releases and patches

Indicators of Compromise (IOCs)

Malicious VBScript MD5: 3D4E88B3BA4D128BB171B74B1F6F641A

Malicious Javascript MD5: 13bea407806390f8c3f823a5ebdcae59

JavaScript downloader scripts

VBS downloader scripts

C&C IPs: