Netskope é nomeada líder no Quadrante Mágico do Gartner® de 2024 para Security Service Edge. Obtenha o Relatório

fechar
fechar
  • Por que Netskope chevron

    Mudando a forma como a rede e a segurança trabalham juntas.

  • Nossos clientes chevron

    A Netskope atende a mais de 3.000 clientes em todo o mundo, incluindo mais de 25 das empresas da Fortune 100

  • Nossos parceiros chevron

    Fazemos parceria com líderes de segurança para ajudá-lo a proteger sua jornada para a nuvem.

Ainda mais alto em execução.
Ainda mais longe na visão.

Saiba por que o 2024 Gartner® Magic Quadrant™ nomeou a Netskope como líder em Security Service Edge pelo terceiro ano consecutivo.

Obtenha o Relatório
A Netskope foi nomeada líder no Quadrante Mágico do Gartner de 2024®™ para o gráfico Security Service Edge para menu
Ajudamos nossos clientes a estarem prontos para tudo

Veja nossos clientes
Woman smiling with glasses looking out window
A estratégia de comercialização da Netskope, focada em Parcerias, permite que nossos Parceiros maximizem seu crescimento e lucratividade enquanto transformam a segurança corporativa.

Saiba mais sobre os parceiros da Netskope
Group of diverse young professionals smiling
Sua Rede do Amanhã

Planeje seu caminho rumo a uma rede mais rápida, segura e resiliente projetada para os aplicativos e usuários aos quais você oferece suporte.

Receba o whitepaper
Sua Rede do Amanhã
Apresentando a plataforma Netskope One

O Netskope One é uma plataforma nativa da nuvem que oferece serviços convergentes de segurança e rede para permitir sua transformação SASE e zero trust.

Saiba mais sobre o Netskope One
Abstrato com iluminação azul
Adote uma arquitetura Secure Access Service Edge (SASE)

O Netskope NewEdge é a maior nuvem privada de segurança de alto desempenho do mundo e oferece aos clientes cobertura de serviço, desempenho e resiliência inigualáveis.

Conheça a NewEdge
NewEdge
Netskope Cloud Exchange

O Cloud Exchange (CE) da Netskope oferece aos clientes ferramentas de integração poderosas para tirar proveito dos investimentos em estratégias de segurança.

Saiba mais sobre o Cloud Exchange
Vídeo da Netskope
A plataforma do futuro é a Netskope

Intelligent Security Service Edge (SSE), Cloud Access Security Broker (CASB), Cloud Firewall, Next Generation Secure Web Gateway (SWG) e Private Access for ZTNA integrados nativamente em uma única solução para ajudar todas as empresas em sua jornada para o Secure Access Service Arquitetura de borda (SASE).

Vá para a plataforma
Vídeo da Netskope
Next Gen SASE Branch é híbrida — conectada, segura e automatizada

Netskope Next Gen SASE Branch converge o Context-Aware SASE Fabric, Zero-Trust Hybrid Security e SkopeAI-Powered Cloud Orchestrator em uma oferta de nuvem unificada, inaugurando uma experiência de filial totalmente modernizada para empresas sem fronteiras.

Saiba mais sobre Next Gen SASE Branch
Pessoas no escritório de espaço aberto
Desenvolvendo uma Arquitetura SASE para Leigos

Obtenha sua cópia gratuita do único guia de planejamento SASE que você realmente precisará.

Baixe o eBook
Mude para serviços de segurança na nuvem líderes de mercado com latência mínima e alta confiabilidade.

Conheça a NewEdge
Lighted highway through mountainside switchbacks
Permita com segurança o uso de aplicativos generativos de IA com controle de acesso a aplicativos, treinamento de usuários em tempo real e a melhor proteção de dados da categoria.

Saiba como protegemos o uso de IA generativa
Ative com segurança o ChatGPT e a IA generativa
Soluções de zero trust para a implementação de SSE e SASE

Conheça o Zero Trust
Boat driving through open sea
Netskope obtém alta autorização do FedRAMP

Escolha o Netskope GovCloud para acelerar a transformação de sua agência.

Saiba mais sobre o Netskope GovCloud
Netskope GovCloud
  • Recursos chevron

    Saiba mais sobre como a Netskope pode ajudá-lo a proteger sua jornada para a nuvem.

  • Blog chevron

    Saiba como a Netskope permite a transformação da segurança e da rede por meio do SSE (Security Service Edge)

  • Eventos e workshops chevron

    Esteja atualizado sobre as últimas tendências de segurança e conecte-se com seus pares.

  • Security Defined chevron

    Tudo o que você precisa saber em nossa enciclopédia de segurança cibernética.

Podcast Security Visionaries

On Patents, Trolls, and Innovation
In this episode host Emily Wearmouth chats with Suzanne Oliver, an intellectual property expert, and Krishna Narayanaswamy, co-founder and CTO of Netskope, about the world of patents.

Reproduzir o podcast
On Patents, Trolls, and Innovation
Últimos blogs

Leia como a Netskope pode viabilizar a jornada Zero Trust e SASE por meio de recursos de borda de serviço de segurança (SSE).

Leia o Blog
Sunrise and cloudy sky
SASE Week 2023: Sua jornada SASE começa agora!

Replay das sessões da quarta SASE Week anual.

Explorar sessões
SASE Week 2023
O que é o Security Service Edge?

Explore o lado de segurança de SASE, o futuro da rede e proteção na nuvem.

Saiba mais sobre o Security Service Edge
Four-way roundabout
  • Empresa chevron

    Ajudamos você a antecipar os desafios da nuvem, dos dados e da segurança da rede.

  • Liderança chevron

    Nossa equipe de liderança está fortemente comprometida em fazer tudo o que for preciso para tornar nossos clientes bem-sucedidos.

  • Customer Solutions chevron

    Estamos aqui junto com você a cada passo da sua trajetória, assegurando seu sucesso com a Netskope.

  • Treinamento e certificação chevron

    Os treinamentos da Netskope vão ajudar você a ser um especialista em segurança na nuvem.

Apoiando a sustentabilidade por meio da segurança de dados

A Netskope tem o orgulho de participar da Visão 2045: uma iniciativa destinada a aumentar a conscientização sobre o papel da indústria privada na sustentabilidade.

Saiba mais
Apoiando a sustentabilidade por meio da segurança de dados
Pensadores, construtores, sonhadores, inovadores. Juntos, fornecemos soluções de segurança na nuvem de última geração para ajudar nossos clientes a proteger seus dados e seu pessoal.

Conheça nossa equipe
Group of hikers scaling a snowy mountain
A talentosa e experiente equipe de Serviços Profissionais da Netskope fornece uma abordagem prescritiva para sua implementação bem sucedida.

Conheça os Serviços Profissionais
Netskope Professional Services
Proteja sua jornada de transformação digital e aproveite ao máximo seus aplicativos de nuvem, web e privados com o treinamento da Netskope.

Saiba mais sobre Treinamentos e Certificações
Group of young professionals working

Leaky O365 Links: Accidental Exposure in O365 Link Sharing

Aug 18 2020

Did you know that the default “copy link” option in O365 personal accounts generates a public shared link with edit permissions? In this edition, we will cover how link sharing in O365 can lead to the accidental internal and public exposure of sensitive data. 

Netskope Threat Labs have shared a series of posts highlighting the exposure concerns in Google Calendar, Google Groups, Google link sharing, and Zendesk. The exposure concerns we highlight in this post about Office 365 are similar to those in our Google link sharing post, as both of these apps offer similar sharing settings to the user and security settings to the administrator. This blog post details how accidental data exposure happens in Office 365 and details the steps you can take to limit or disable external sharing. 

O365 link sharing

Similar to Google, Microsoft also provides link sharing for a wide range of O365 apps, including OneDrive, Word, Excel, PowerPoint, OneNote, Calendar, and Sway. In each app, users can choose between view or edit permissions, and grant those permissions to “Anyone with the link,” “Specific people,” or “Only people in your organization” (only for users in Business accounts) as shown in Figure 1.

Screenshot of O365 link sharing settings
Figure 1: O365 link sharing settings

Unlike Google, O365 users are provided with an option to set a password for the link sharing as shown in Figure 2.

Screenshot showing expiration date and password option for link sharing
Figure 2: Expiration date and password option for link sharing

In O365 Business accounts, users are provided with an additional set of link sharing settings as shown in Figure 3.

Screenshot showing link sharing settings in O365 Business accounts
Figure 3: Link sharing settings in O365 Business accounts

The link sharing settings have the following options:

  • Anyone with the link → for sharing a link that allows everyone to access.
  • People in [your organization] with the link → for sharing a link that everyone within your organization can access.
  • People with existing access → for sharing with users who already have access granted explicitly to them
  • Specific people → for sharing with specific authenticated users either inside or outside your organization

Accidental exposure

Link sharing can lead to accidental exposure when a user sets inappropriately broad permissions when sharing a document. For example, an O365 personal account user might use the “Copy link” option to share a document with a friend. In this case, it would have been more secure to share the file explicitly with only that friend. If the link gets forwarded to someone else or shared publicly, anyone with the link can edit the document. The workflow that has the default permission allowing anyone with the link to edit, as shown in Figure 4.

Screenshot showing "copy link" option in O365 personal accounts
Figure 4: “Copy link” option in O365 personal accounts

In Business accounts, the default settings allow users to share documents publicly, the same way they can in personal accounts. However, administrators can restrict how broadly users can share documents, from the “most permissive” setting to the “least permissive” setting that only allows documents to be shared internally, pictured in Figure 5.

Screenshot showing the most permissive external sharing settings
Figure 5: Most permissive external sharing settings

Administrators can also configure an option to allow access to authenticated external users (or guests) using an invitation code to verify their identity that can be redeemed only once.

Even when the “least permissive” setting is chosen, users can still share documents with everyone within the organization via link sharing. This allows everyone in the organization to access and edit the document by default. This can cause an unwanted internal exposure of confidential data. Even within the organization, it is more secure to share documents with individual users to prevent potential insider threats and to only use “edit” permissions when necessary.

Office 365 Usage and Sharing Statistics

In the Netskope Security Cloud platform, OneDrive for Business is one of the most popular apps. On average, 26% of the total users on the platform accessed OneDrive for Business each day over the past six months.

Sharing documents is a common activity among OneDrive for Business users. In total, 23% of Office 365 for Business users shared documents with other individual users within their org, and 3% shared documents with other individual users outside their org. This is the approach we recommend — by specifying individuals, you limit access only to those users. Another 8% used the “Anyone with link” sharing option to share documents either internally or externally. For personal OneDrive accounts, the amount of sharing via link was lower, with only 1% of personal account users sharing files publicly.

The two biggest risks with link sharing are:

  1. Anyone can access and edit a file if they get their hands on the link, even if you didn’t intend to share the document with them. This is a risk even for sensitive internal data not intended to be shared with everyone in the organization.
  2. If the link is externally accessible, users can access the links even after they leave the organization.

Figure 6 shows a breakdown of the files shared publicly by type. The majority of the documents are Microsoft Office formats, with spreadsheets being the most common. Some other formats, including PDFs and images, are also represented in the “Other” slice. Some spreadsheets, documents, and other files contained confidential data that was likely not intended to be shared publicly.

Pie chart showing the different file types seen in public share links
Figure 6: File types seen in public share links

O365 link sharing – Recommended settings

When you use link sharing, you relinquish control over who can access your files — anyone who gets their hands on a link can access a file, whether you intended them to or not. We recommend to always share files with individual users whenever possible. If sharing files publicly via links, disable editing unless you want everyone to be able to edit the document.  

Individual users should disable the “allow editing” option in the link sharing settings and add a name or email address in the Send Link dialog, as shown in Figure 7. Even if you are using a business account, we still recommend sharing documents explicitly with individual users whenever possible, and disabling “allow editing” even if the document is only shared internally.

Screenshot showing recommended link sharing option for O365 personal accounts
Figure 7: Recommended link sharing option for O365 personal accounts

Enterprise administrators can audit the sharing permissions and limit link sharing with “least permissive” sharing shown in Figure 8.

Screenshot showing the least permissive sharing for O365 SharePoint and OneDrive
Figure 8: Least permissive sharing for O365 SharePoint and OneDrive

The link sharing settings mentioned in Figure 6 only apply to OneDrive and SharePoint and not other O365 apps. As the external link sharing option exists in other O365 apps like Sway (for example), enterprise administrators should also audit and disable external sharing for these other apps individually from within the  Microsoft 365 admin center

Conclusão

This edition of our leaky cloud apps series provided a detailed synopsis of how confidential information gets leaked through misconfigured O365 link sharing. Misconfigured sharing controls can lead to data exposure. The data can be copied, reused, and also benefit adversaries in gaining access to additional data and infrastructure. We recommend auditing link sharing options and restricting access to specific users to avoid accidental exposure. For more information about sharing permissions, we recommend reading the Microsoft article describing how to audit your own settings.

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.’

Stay informed!

Subscribe for the latest from the Netskope Blog