Restricting which managed identities can access an Azure applicationOn Azure, we can use managed identities and AzureAD applications to authenticate service-to-service authentication. But how can we ensure that only certain managed identities can obtain access tokens for an application? Continue »
Playing certificate authority: Using Cloud KMS to sign certificate signing requestsLast time, we looked at how we can use a Cloud KMS asymmetric signing key to create a self-signed X.509 certificate. But we’re not limited to self-signed certificates. We can use Cloud KMS to sign other certificate signing requests too, just like a certificate authority (CA). Continue »
Using a Cloud KMS asymmetric signing key to create an X.509 certificateAfter you create an asymmetric signing key in Cloud KMS, you can download the key pair’s public key. The key is provided in PEM format – that’s pretty standard and all you need in many use cases. But especially when dealing with third party services, you sometimes need an X.509 certificate instead of a plain public key. Continue »
Best practices for managing service account keysService accounts play a key role in Google Cloud IAM, and there are multiple ways how service accounts can authenticate. One of them is by using a service account key – but service account keys turn into a security risk if they aren’t managed carefully. Continue »
Using IAM to control SSH and RDP accessWhenever we grant users SSH or RDP access to VM instances, we have to ensure that access is revoked when the user changes teams or leaves the organization. This is easier said than done. Continue »
Limiting the validity of service account keysWhen you create a service account key, Google Cloud doesn’t let you specify an expiry date. The key stays valid until you either delete the key or the entire service account. But there’s a way to limit the validity of a service account key. Continue »
Using a CNG-backed key as service account keyLast time, we looked at how you can use a CryptoAPI-backed key as a service account and use it to authenticate. Now let’s see how you can do the same with CNG. Continue »
Using a CryptoAPI-backed key as service account keyUsing service account keys to authenticate a service account is generally discouraged on Google Cloud, but sometimes difficult to avoid. The most common way to use service account keys is to create a new key by using the Cloud Console or gcloud, but you can also upload existing keys, including CryptoAPI-based keys. Continue »
Azure AD defaults to SAML Logout, but not all apps support thatWhen you create an enterprise app in Azure AD and configure SAML-based single sign-on, Azure AD assumes that the application also supports SAML for sign-out – but as it turns out, not all apps do. Continue »
Azure AD federation metadata, with or without authenticationWhen working with cloud services, you occasionally encounter two APIs that essentially do the same thing, but require different authentication or permissions. Such cases tend to pique my interest. Continue »
Limit metadata server access to specific Windows users or processesBy default, access to the Compute Engine metadata server is not limited to specific processes or users on a VM, even low-privilege processes can request service account credentials. Can we limit metadata server access to specific Windows users or processes? Continue »
Best practices for using, managing, and securing service accounts on Google CloudService accounts play a key role in Google Cloud IAM, but they are easy to get wrong. If you’re not careful, you quickly end up with over-permissioned service accounts, accounts that are used across multiple applications, and service account keys being spread all across your environment. Continue »
Using Google Cloud’s “Set Windows password” function on a domain controllerWhat happens if you use the “Set Windows password” function on a domain controller? Continue »
Preventing users from requesting Windows credentials on GCPAfter creating a Windows VM on Google Cloud, users can use the Cloud Console or IAP Desktop to request login credentials. But what are the risks of letting users generate credentials, and is there a way to prevent them from doing so? Continue »
What does the email_verified claim indicate in Google ID Tokens?When you authenticate a user by using OpenID Connect and request the email scope, most identity providers add two additional claims to the ID Token, email and email_verified. The email claim does not need much explanation – but what about email_verified, what does this claim indicate and how does Google populate it?
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Authenticating users in tools or desktop appsIf your plan is to develop a tool or desktop app instead of a server-side application, the benefits of application default credentials are less obvious and reusing the user’s personal gcloud credentials instead might seem attractive. But there are some pitfalls. Continue »
Application default credentials vs your personal gcloud credentialsgcloud manages two sets of credentials, your personal credentials and application default credentials. Having two separate credentials might seem redundant and can cause surprises the first time you use one of the Google Cloud client libraries. But the two credentials serve different purposes. Continue »
Dealing with credentials when using the Google Cloud client libraries (.NET edition)Google APIs use OAuth 2.0 for authentication and authorization. To call an API, you first have to obtain an access token for the right scope and then pass it to the respective API by using the Authorization HTTP header.
But the trouble with access tokens is that they are short-lived, and you somehow have to deal with expiring tokens…
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Impact of GCP session length on OAuth clientsOnce you’ve signed in on google.com, the Cloud Console, or any other Google site, your browser session remains valid for multiple days. Not being prompted to sign in over and over again is convenient and at least in typical consumer scenarios, the risk that comes along with keeping the session is limited.
Things can look different in a corporate scenario where users might have access to sensitive data. Keeping sessions alive for 14 days (which is the default) might seem a little risky and might not be in line with an enterprise’s idea of security. G Suite Business and Cloud Identity Premium therefore allow you to change the default session length to a different period such as 8 hours. This setting applies to all Google services, not only GCP.
Recently, Google introduced another way to control session lifetime by allowing you to control the session length for Cloud Console and gcloud sessions.
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New version of the Cloud IAP plugin for Remote Desktop releasedA few days ago, I released version 1.1.22 of the Cloud IAP plugin for Remote Desktop on Github.
The three main new features in this release are: