Session management
Session management is an anti-denial of service (DoS) best practice for API security. A session represents the amount of time a visitor spends on your site and is not related to how long Admin users or customers are logged in to their accounts.
A session is a sequence of network HTTP request and response transactions associated with the same user. It is a way to associate a client (Admin) with their data when they access the server. Sessions are used to establish variables, such as access rights and localization settings, which apply to every interaction a user has with a web application during the session.
Session size
Use the following configuration settings to limit the maximum session size for Admin users and storefront visitors:
- Max Session Size in Admin—Limit the maximum sessions size in bytes. Use
0to disable. - Max Session Size in Storefront—Limit the maximum sessions size in bytes. Use
0to disable.
256000 bytes (or 256 KB).To configure maximum session size:
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On the Admin sidebar, go to Stores > Settings > Configuration.
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In the left panel, expand Advanced and choose System.
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Expand
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Enter new session sizes in bytes.
note warning WARNING Setting the value too low can cause issues. If you set either of the options below the default of 256000 bytes, you see a warning message. If you click No, the system changes the value to 256000. -
Click Save Config.
Admin sessions
If you exceed the maximum session size, an error message is displayed and the system logs the session size constraint to the var/log directory.
If you lose access to the Admin after setting the session size too low, use the CLI to reset the configuration:
bin/magento config:set system/security/max_session_size_admin 256000
Storefront sessions
If you exceed the maximum session size, no error displays but the system logs the session size constraint to the var/log directory.
Session validation
Adobe Commerce and Magento Open Source allow you to validate session variables as a protective measure against possible session fixation attacks or attempts to poison or hijack user sessions. The Session Validation Settings determine how session variables are validated during each store visit and if the session ID is included in the URL of the store.
For technical information, see Use Redis for session storage in the Configuration Guide.
The validation checks that visitors are who they say they are by comparing the value in the validation variables against the session data that is stored in $_SESSION data for the user. Validation fails if the information is not transmitted as expected, and the corresponding variable is empty. Depending on the session validation settings, if a session variable fails the validation process, the client session immediately terminates.
Enabling all validation variables can help prevent attacks, but might also impact the performance of the server. By default, all session variable validation is disabled. We recommend that you experiment with the settings to find the best combination for your Adobe Commerce or Magento Open Source installation. Activating all validation variables might prove to be unduly restrictive, and could prevent access to customers who have Internet connections that pass through a proxy server or originate from behind a firewall. To learn more about session variables and their use, see the system administration documentation for your Linux® system.
To configure the session validation:
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On the Admin sidebar, go to Stores > Settings > Configuration.
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In the left panel, expand General and choose Web.
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Expand
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Set each of the configuration options:
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Validate REMOTE_ADDR — Set to
Yesto verify that the IP address of a request matches what is stored in the$_SESSIONvariable. -
Validate HTTP_VIA — Set to
Yesto verify that the proxy address of an incoming request matches what is stored in the$_SESSIONvariable. -
Validate HTTP_X_FORWARDED_FOR — Set to
Yesto verify that the forwarded-for address of a request matches what is stored in the$_SESSIONvariable. -
Validate HTTP_USER_AGENT — Set to
Yesto verify that the browser or device that is used to access the store during a session matches what is stored in the$_SESSIONvariable.
-
-
When complete, click Save Config.
Admin session lifetime
As a security measure, the Admin is initially set to time out after 900 seconds (15 minutes) of keyboard inactivity. You can adjust the lifetime of the session to fit your work style.
To adjust Admin session lifetime:
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On the Admin sidebar, go to Stores > Settings > Configuration.
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Scroll down and expand Advanced in the left side panel.
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Click Admin.
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Expand
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For Admin Session Lifetime (seconds), enter the number of seconds that a session remains active before it times out.
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When complete, click Save Config.## Admin session lifetime
As a security measure, the Admin is initially set to time out after 900 seconds (15 minutes) of keyboard inactivity. You can adjust the lifetime of the session to fit your work style.
To adjust Admin session lifetime:
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On the Admin sidebar, go to Stores > Settings > Configuration.
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Scroll down and expand Advanced in the left side panel.
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Click Admin.
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Expand
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For Admin Session Lifetime (seconds), enter the number of seconds that a session remains active before it times out.
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When complete, click Save Config.