SSEへのジャーニーを加速します。 RSAでNetskopeブースにお越しください

  • セキュリティサービスエッジ製品

    高度なクラウド対応の脅威から保護し、あらゆるベクトルにわたってデータを保護します。

  • Borderless SD-WAN

    すべてのリモートユーザー、デバイス、サイト、クラウドへの安全で高性能なアクセスを自信を持って提供します。

  • プラットフォーム

    世界最大のセキュリティプライベートクラウドでの比類のない可視性とリアルタイムデータおよび脅威保護。

ネットスコープ、2022年Gartner社のセキュリティ・サービス・エッジ(SSE)のマジック・クアドラントでリーダーの1社と位置付けられる

レポートを読む 製品概要に移動
Netskope Gartner マジック・クアドラント 2022 SSEリーダー
Gartner® Quick Answer:NetskopeのInfiot買収はSD-WAN、SASE、SSEプロジェクトにどのような影響を与えますか?

レポートを読む
Gartner quick answer
Netskope は、データと脅威の保護、および安全なプライベートアクセスを実現するための機能を統合した、最新のクラウドセキュリティスタックを提供します。

プラットフォームを探索する
大都市の俯瞰図
  • 変身

    デジタルトランスフォーメーションを保護します。

  • セキュリティの近代化

    今日と明日のセキュリティの課題に対応します。

  • フレームワーク

    サイバーセキュリティを形作る規制の枠組みを採用する。

  • 業界ソリューション

    Netskopeは、クラウドに安全に移行するためのプロセスを世界最大規模の企業に提供しています。

最小の遅延と高い信頼性を備えた、市場をリードするクラウドセキュリティサービスに移行します。

詳しくはこちら
Lighted highway through mountainside switchbacks
シングルパスSSEフレームワークを使用して、他のセキュリティソリューションを回避することが多い脅威を防止します。

詳しくはこちら
Lighting storm over metropolitan area
SSEおよびSASE展開のためのゼロトラストソリューション

詳しくはこちら
Boat driving through open sea
Netskopeは、クラウドサービス、アプリ、パブリッククラウドインフラストラクチャを採用するための安全でクラウドスマートかつ迅速な旅を可能にします。

詳しくはこちら
Wind turbines along cliffside
  • 導入企業

    Netskopeは、フォーチュン100の25以上を含む世界中の2,000以上の顧客にサービスを提供しています。

  • カスタマーソリューション

    お客様のため、Netskopeでお客様の成功を確実にすべく、あらゆるステップを共に歩んでまいります。

  • トレーニングと認定

    Netskope training will help you become a cloud security expert.

私たちは、お客様が何にでも備えることができるように支援します

お客様を見る
Woman smiling with glasses looking out window
Netskopeの有能で経験豊富なプロフェッショナルサービスチームは、実装を成功させるための規範的なアプローチを提供します。

詳しくはこちら
Netskopeプロフェッショナルサービス
Netskopeトレーニングで、デジタルトランスフォーメーションの旅を保護し、クラウド、ウェブ、プライベートアプリケーションを最大限に活用してください。

詳しくはこちら
Group of young professionals working
  • リソース

    クラウドへ安全に移行する上でNetskopeがどのように役立つかについての詳細は、以下をご覧ください。

  • ブログ

    Netskopeがセキュリティサービスエッジ(SSE)を通じてセキュリティとネットワークの変革を可能にする方法を学びましょう。

  • イベント&ワークショップ

    最新のセキュリティトレンドを先取りし、仲間とつながりましょう。

  • 定義されたセキュリティ

    サイバーセキュリティ百科事典で知っておくべきことすべて。

セキュリティビジョナリーポッドキャスト

エピソード 10: 透明性によるセキュリティ関係の構築
In this episode, Mike and Andreas discuss aligning with works councils, forging business relationships through transparency, and embedding security into value streams.

ポッドキャストを再生する
Building Security Relationships Through Transparency
Netskopeがセキュリティサービスエッジ(SSE)機能を介してゼロトラストおよびSASEジャーニーを実現する方法に関する最新情報をお読みください。

ブログを読む
Sunrise and cloudy sky
RSAのネツコペ

今年のRSAカンファレンスでNetskopeブースにお越しいただき、SASEとゼロトラストに関するお話をお聞きください。サウスホールのブースにお立ち寄りいただき、エキスパートとの情報交換や、講演セッションへの登録など、ぜひイベントにご参加ください!

詳しくはこちら
RSA logo
セキュリティサービスエッジとは何ですか?

SASEのセキュリティ面、ネットワークとクラウドでの保護の未来を探ります。

詳しくはこちら
Four-way roundabout
  • 会社概要

    クラウド、データ、ネットワークセキュリティの課題の先取りをサポート

  • ネットスコープが選ばれる理由

    クラウドの変革とどこからでも機能することで、セキュリティの機能方法が変わりました。

  • リーダーシップ

    ネットスコープの経営陣はお客様を成功に導くために全力を尽くしています。

  • パートナー

    私たちはセキュリティリーダーと提携して、クラウドへの旅を保護します。

Netskopeは仕事の未来を可能にします。

詳しくはこちら
Curvy road through wooded area
Netskopeは、組織がゼロトラストの原則を適用してデータを保護できるように、クラウド、データ、およびネットワークのセキュリティを再定義しています。

詳しくはこちら
Switchback road atop a cliffside
思想家、建築家、夢想家、革新者。 一緒に、私たちはお客様がデータと人々を保護するのを助けるために最先端のクラウドセキュリティソリューションを提供します。

当社のチーム紹介
Group of hikers scaling a snowy mountain
Netskopeのパートナー中心の市場開拓戦略により、パートナーは企業のセキュリティを変革しながら、成長と収益性を最大化できます。

詳しくはこちら
Group of diverse young professionals smiling

Coin mining malware heads to the cloud with Zminer

Aug 24 2017
Tags
Bitcoin
CASB
Cloud Access Security Broker
Cloud Security
coin mining
Data Loss Prevention Software

Netskope Threat Research Labs has detected several samples related to a coin miner malware named Zminer. The kill chain begins with the delivery of a drive-by download Zminer executable that downloads payloads from Amazon S3 cloud storage to a victim’s machine and then uses the machine’s computing resources to perform coin mining. Netskope Threat Research Labs detects the parent file as Gen:[email protected] and the downloaded payloads as Backdoor.generckd.12153334, Backdoor.generckd.5229808 and Application.BitCoinMiner.RH

Overview

“Coin mining” is a term that became popular after the introduction of Bitcoin. Bitcoin is the first decentralized digital currency invented by a programmer named Satoshi Nakamoto. It does not make use of financial institutions as it is solely tied to the Bitcoin addresses, so no central authority is necessary to control the currency. Transactions are made by digitally exchanging encrypted hash codes across a peer-to-peer (P2P) network between users. Each user’s bitcoins are stored in a program called a digital wallet, which also holds the user’s address for sending and receiving bitcoins and a private key only known to the user as an additional layer of protection. There are several coins similar to Bitcoin that we will explain in the cryptocurrencies section

Coin Mining

Coin mining is a procedure for earning coins by mining hardware based on a fixed amount of computing power. This is performed using a coin miner. Anyone with access to the internet and suitable hardware can participate in mining. Depending on the hardware and resources available, several mining methods like CPU mining, GPU mining, FPGA mining, ASC mining and cloud mining are used for coin mining. Upon verification of these mining transactions, a coin is generated using a public ledger, known as the blockchain.

Mining coins using standard computer hardware has become unprofitable. Pooled mining approach has been introduced to compensate this problem. Pooled mining is a mining approach where groups of individual miners contribute to the generation of a block, and then split the block reward according to the contributed processing power. A comprehensive list of some of the pools and their payout methods are documented in this Wikipedia article.

Cryptocurrency

A cryptocurrency works as a digital asset exchange medium using cryptography. Bitcoin is the first decentralized cryptocurrency, which has led to the creation of several cryptocurrencies. There are more than 900 cryptocurrencies as of 11 July 2017 documented in Wikipedia.

Cryptocurrency Valuation

Cryptocurrencies have a market cap of nearly $150 billion with Bitcoin taking the top spot. Currently valued around $4,000 per bitcoin and on a fast pace towards the $5,000 per bitcoin valuation, the chart of Bitcoin’s value is shown in Figure 1.

Figure 1: Bitcoin Price Chart

Cybercriminals and Cryptocurrency

The massive growth of the internet as a money model for cryptocurrencies has attracted the interest of cybercriminals. Malware is implanted in a victim’s machine to perform the following:

  • Mine bitcoins using the machine’s computing resources or even a company’s server power
  • Steal the victim’s Bitcoin wallet
  • Pay ransom using Bitcoin to recover the ransomware-encrypted files

Analysis of Zminer

On execution, Zminer downloads two payloads from Amazon S3 Cloud storage named Claymore+CryptoNote+CPU+Miner+v3.5+Beta+-+POOL.zip and Manager.exe as shown in Figure 2 and Figure 3.

Figure 2: Claymore CryptoNote CPU Miner payload from Amazon S3 Cloud Storage

Figure 3: Manager.exe payload from Amazon S3 Cloud Storage

Analysis of the payloads

NsCpuCNMiner32.exe

NsCpuCNMiner32.exe is a Monero (XMR) CPU miner executable dropped in the %Application Data%\Claymore CryptoNote CPU Miner v3.5 Beta – POOL\ directory. Monero (XMR) is an open-source cryptocurrency that uses the CryptoNote technology. This makes anyone with a computer able to mine it with a simple processor. The hashing power can be distributed throughout an entire network as long as the mining is within a small/medium pool. The Monero (XMR) CPU miner executable is a command line application that has several functions as shown in Figure 4.

Figure 4: Monero (XMR) CPU miner executable options

Manager.exe

Manager.exe ensures that Zminer will be able to carry out the mining operation. This is dropped in %windir% on installation. The binary contains an encrypted string that is decrypted during runtime as shown in Figure 5.

Figure 5: Decrypted Amazon S3 URL with the payload

The decrypted string is a URL that downloads another binary named DBupdater.exe using Amazon S3 cloud storage. The packet capture of the download activity is shown in Figure 6.

Figure 6: DBupdater.exe payload from Amazon S3 cloud storage

DBUpdater.exe

DBupdater.exe creates a log file named log.txt, that contains several details of the victim’s machine. The file is then uploaded to the C&C server with IP 54.214.246[.]97. The IP is registered to Amazon S3 whose resolve host is ec2-54-214-246-97.us-west-2.compute[.]amazonaws.com. The packet capture of the download activity is shown in Figure 7.

Figure 7: Data uploaded to the C&C 54.214.246[.]97

The log.txt file is deleted once the data is uploaded to the C&C

Driver.job, Manager.job

Driver.job and Manager.job job files contain instructions for the Windows Task Scheduler to execute. These are dropped in %windir%\Tasks\ folder and is only created in Windows XP. An example of the job file created by driver.job is shown in Figure 8.

Figure 8: %windir%\Tasks\Driver.job

Zminer in operation

Once the required components are downloaded and installed in the victim’s machine, Zminer begins the mining operation.

To ensure smooth functionality, Zminer disables the inbuilt Windows Defender security service by adding keys in the registry as shown in Figure 9.

Figure 9:  Zminer disabling Windows Defender

The mining is performed using the Nanopool “stratum+tcp://xmr-eu1.nanopool.org” in the victim’s machine with a user address that is hardcoded in the binary which is run via command line as shown in Figure 10.

Figure 10:  Nanopool mining details using stratum+tcp://xmr-eu1.nanopool.org

The packet capture of the mining operation is shown in Figure 11.

Figure 11:  Details of the mining operation

We accessed the website,  https://xmr.nanopool.org/blocks and found the details of the user address hard coded in the binary. The details of the user address are shown in Figure 12.

Figure 12: Details of the user address hard coded in the binary

At the time of writing, the user address has been paid 101.736078074478 XMR. XMR is the code for Monero. It is currently valued close to 80 USD per XMR.

Depending on the operating system, Zminer downloads a version of nheqminer for a 64 bit Windows machine using Amazon S3 Cloud Storage as shown in Figure 13.

Figure 13: Nheqminer payload from Amazon S3 Cloud Storage

The mining is performed using the Nanopool “zec-eu1.nanopool.org” in the victim’s machine with a user address that is hard coded in the binary which is run via command line as shown in Figure 14.

Figure 14: Nanopool mining details using zec-eu1.nanopool.org

We accessed the website, https://zec-bitcore1.trezor.io  and found out details of the other user address hard coded in the binary. The details of the user address are shown in Figure 15.

Figure 15: Details of the other user address hard coded in the binary

At the time of writing, the other user address has been paid 44.12392799 ZEC. ZEC is the code for Zcash. It is currently valued close to 31 USD per ZEC.

Since the mining operation usually involves a lot of computing power, the CPU usage will be extensively dominated by the miner. As a result, the machines or workstations start functioning abnormally slow. An example of the CPU utilization with Zminer using NsCpuCNMiner is shown in Figure 16.

Figure 16: Zminer hogging CPU usage

Similar Zminer Strains

During our research, we identified similar strains of Zminer. While investigating the samples, one of the sample detected by Netskope Threat Protection as Backdoor.generckd.5229808 had the email address mentioned in the mining operation as shown in Figure 17.

Figure 17: Possible email address associated with the mining operation

Conclusion

The extensive adoption of cryptocurrency for purchases and trading has attracted the attention of cybercriminals. Since a crypto mining operation involves a lot of computing power and resources, cyber criminals implant miners in the victims’ machines to generate revenue. These attacks can be effectively carried out in a corporate environment as the machines and workstations have good hardware with abundant supply of electricity. This can lead to severe consequences as the corporate resources and data used for performing a coin mining operation can be used for any cybercriminal or illegal action. Though Bitcoin is considered illegal in several countries, the use of coin miners in a corporate instance is potentially unsafe. Organizations should have policies to detect the presence of bitcoins and mining pools. As enterprises are rapidly adopting the use of Cloud and Cloud services, the need for a threat-aware solution and defensive mechanism for SSL inspection is required. Netskope has disclosed to Amazon S3 cloud storage about the URLs hosting the Zminer payloads.

General Recommendations

Netskope recommends the following to combat cloud malware and threats:

  • Detect and remediate cloud threats using a threat-aware cloud access security broker 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 applications for malware
    • Scan all uploads from remote devices to sanctioned cloud applications for malware
    • Scan all downloads from unsanctioned cloud applications for malware
    • Scan all downloads from unsanctioned instances of sanctioned cloud applications for malware
    • Enforce quarantine/block actions on malware detection to reduce user impact
    • Block unsanctioned instances of sanctioned/well known cloud apps, 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
  • Administrators can create firewall rules to block bitcoin pools documented in the Wikipedia article
  • 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 tools updated with the latest releases and patches
author image
Ashwin Vamshi
Ashwin Vamshi is a Security Researcher with innate interest in targeted attacks and malwares using cloud services. He is primarily focusing in identifying new attack vectors and malwares, campaigns and threat actors using ‘cloud as an attack vector.’