Expire Shared Access Signature Tokens (2024)

FAQs

What is a shared access signature token? ›

A shared access signature is a token that is appended to the URI for an Azure Storage resource. The token that contains a special set of query parameters that indicate how the resources may be accessed by the client.

The validity interval for the SAS is calculated by subtracting the date/time value of the signed start field from the date/time value of the signed expiry field. If the resulting value is less than or equal to the recommended upper limit, then the SAS is in compliance with the SAS expiration policy.

Providing a Shared Access Signature (SAS) token to these clients allows them to access your resources for a specified period of time. To protect your storage account resources against unapproved access, the validity period configured for your SAS token should be set as low as possible, ideally no longer than an hour.

If a SAS is compromised, you will want to revoke that SAS as soon as possible. To revoke a user delegation SAS, revoke the user delegation key to quickly invalidate all signatures associated with that key.

A shared access signature is a signed URI that points to one or more storage resources and includes a token that contains a special set of query parameters. The token indicates how the resources may be accessed by the client.

Shared Access Signatures provide granular control to your storage. Access keys give you full rights to everything in your storage account, but with SAS you're able to limit the access capabilities of its users.

Physical Card: The expiry date is prominently displayed on the front of your credit card. It is usually printed as a two-digit month followed by a two-digit year (MM/YY). This indicates the month and year when your card will expire.

Look for a date accompanied with “use by,” “sell by,” or “best by.” ^{X Trustworthy Source American Heart Association Leading nonprofit that funds medical research and public education Go to source} Check the bottom of the product, the sides of the container, the lid, and the necks of bottles.

SAS licenses expire every year on a specific date, after which time SAS will not will not launch. You must purchase SAS again then follow the steps below to renew your license (no need to reinstall). If you need to install the SAS software (not just renew the license), please see SAS Installation Instructions.

As mentioned, for security purposes, access tokens may be valid for a short amount of time. Once they expire, client applications can use a refresh token to "refresh" the access token.

Do access tokens expire? ›

Access tokens to expire, their default lifetime is ~1h and can be configured to up to ~24h (28h).

Give tokens an expiration: Technically, once a token is signed, it is valid forever—unless the signing key is changed or expiration explicitly set.

There are two types of SAS: service-level SAS and account-level SAS. 1. Service-level SAS: This type of SAS grants access to a specific resource, such as a file or a blob, and has a limited scope.

SAS tokens become a serious security risk when misconfigured, especially when sharing information with external entities. If compromised, a misconfigured SAS token can make the entire system vulnerable.

If a SAS token gets into the wrong hands, the perpetrator can have prolonged or even indefinite access to your resources, potentially leading to data breaches, unauthorized transactions, or other forms of cybercrime.

You can provide a shared access signature to clients who shouldn't be trusted with your storage account key but who need access to certain storage account resources. By distributing a SAS URI to these clients, you can grant them access to a resource for a specified period of time, with a specified set of permissions.

SAS tokens are used to grant permissions to storage resources, and should be protected in the same manner as an account key. Operations that use SAS tokens should be performed only over an HTTPS connection, and SAS URIs should only be distributed on a secure connection such as HTTPS.