This section deals with various steps that you should take to ensure that your AEM installation is secure when deployed. The checklist is meant to be applied from top to bottom.
Further information is also available about the most dangerous security threats as published by Open Web Application Security Project (OWASP).
There are some additional security considerations applicable at the development phase.
For more information, see Running AEM in Production Ready Mode.
Enabling the HTTPS transport layer on both author and publish instances is mandatory for having a secure instance.
See the Enabling HTTP Over SSL section for more information.
Ensure that you have installed the latest Security Hotfixes provided by Adobe.
Adobe recommends after installation that you change the password for the privileged AEM
admin accounts (on all instances).
These accounts include:
After you have changed the password for the AEM admin account, use the new password when accessing CRX.
admin password for the OSGi Web console
This change is also applied to the admin account used for accessing the Web console, so use the same password when accessing that.
These two accounts use separate credentials and having distinct, strong password for each is vital to a secure deployment.
The password for the AEM admin account can be changed via the Granite Operations - Users console.
Here you can edit the
admin account and change the password.
Changing the admin account also changes the OSGi web console account. After changing the admin account, you should then change the OSGi account to something different.
Aside from the AEM
admin account, failing to change the default password for the OSGi web console password can lead to:
For more information on changing the web console password, see Changing the OSGi web console admin password below.
Change the password used for accessing the Web console. Use an OSGI configuration to update the following properties of the Apache Felix OSGi Management Console:
See OSGI configuration for full details of configuring OSGi settings.
To change the OSGi web console admin password:
Using the Tools, Operations menu, open the Web Console and navigate to the Configuration section.
For example, at
Navigate to, and open, the entry for Apache Felix OSGi Management Console.
Change the user name and password.
Adobe recommends defining custom error handler pages, especially for 404 and 500 HTTP Response codes to prevent information disclosure.
See How can I create custom scripts or error handlers for more details.
AEM Dispatcher is a critical piece of your infrastructure. Adobe recommends that you complete the Dispatcher security checklist.
Using the Dispatcher you must disable the “.form” selector.
A standard installation of AEM specifies
admin as the user for transport credentials within the default replication agents. Also, the admin user is used to source the replication on the author system.
For security considerations, both should be changed to reflect the particular use case at hand, with the following two aspects in mind:
The transport user must not be the admin user. Rather, set up a user on the publish system that has only access rights to the relevant portions of the publish system and use that user’s credentials for the transport.
You can start from the bundled replication-receiver user and configure this user’s access rights to match your situation
The replication user or Agent User Id also must not be the admin user, but a user who can only see content that is replicated. The replication user is used to collect the content to be replicated on the author system before it is sent to the publisher.
AEM 6 introduces the new Operations Dashboard, aimed at aiding system operators troubleshoot problems and monitor the health of an instance.
The dashboard also comes with a collection of security health checks. It is recommended you check the status of all the security health checks before going live with your production instance. For more information, consult the Operations Dashboard documentation.
All example content and users (for example, the Geometrixx project and its components) should be uninstalled and deleted completely on a productive system before making it publicly accessible.
We.Retail applications are removed if this instance is running in Production Ready Mode. If this scenario is not the case, you can uninstall the sample content by going to Package Manager, then searching for, and uninstalling, all
See Work With Packages.
These development OSGi bundles should be uninstalled on both author and publish productive systems before making them accessible.
The AEM Developer Tools deploy the Apache Sling Tooling Support Install (org.apache.sling.tooling.support.install).
This OSGi bundle should be uninstalled on both author and publish productive systems before making them accessible.
AEM 6.1 ships with a mechanism that helps protect against Cross-Site Request Forgery attacks, called the CSRF Protection Framework. For more information on how to use it, consult the documentation.
To address known security issues with Cross-Site Request Forgery (CSRF) in CRX WebDAV and Apache Sling, add configurations for the Referrer filter to use it.
The referrer filter service is an OSGi service that lets you configure the following:
which http methods should be filtered
whether an empty referrer header is allowed
and a list of servers to be allowed in addition to the server host.
By default, all variations of localhost and the current host names the server is bound to are in the list.
To configure the referrer filter service:
Open the Apache Felix console (Configurations) at:
In the Configurations menu, select:
Apache Sling Referrer Filter
Allow Hosts field, enter all hosts that are allowed as a referrer. Each entry must be of the form
https://allowed.server:80allows all requests from this server with the given port.
0as the port number.
Allow Empty field, if you want to allow empty/missing referrer headers.
Adobe recommends that you provide a referrer while using command-line tools such as
cURL instead of allowing an empty value as it might expose your system to CSRF attacks.
Edit the methods that this filter uses for checks with the
Filter Methods field.
Click Save to save your changes.
Some OSGI settings are set by default to allow easier debugging of the application. Change such settings on your publish and author productive instances to avoid internal information leaking to the public.
All the settings below, except for The Day CQ WCM Debug Filter, are automatically covered by the Production Ready Mode. As such, Adobe recommends that you review all the settings before deploying your instance in a productive environment.
For each of the following services, the specified settings must be changed:
When working with AEM, there are several methods of managing the configuration settings for such services; see Configuring OSGi for more details and the recommended practices.
A denial of service (DoS) attack is an attempt to make a computer resource unavailable to its intended users. This attack is often done by overloading the resource; for example:
A flood of requests from an external source.
A request for more information than the system can successfully deliver.
For example, a JSON representation of the entire repository.
By requesting a content page with an unlimited number of URLs, The URL can include a handle, some selectors, an extension, and a suffix - any of which can be modified.
.../en.html can also be requested as:
All valid variations (for example, return a
200 response and are configured to be cached) are cached by the Dispatcher, eventually leading to a full file system and no service for further requests.
There are many points of configuration for preventing such attacks, but only those points that relate to AEM are discussed here.
Configuring Sling to Prevent DoS
Sling is content-centric. Processing is focused on the content as each (HTTP) request is mapped onto content in the form of a JCR resource (a repository node):
See Sling Request Processing for more information.
This approach makes Sling powerful and flexible, but as always it is the flexibility that must be carefully managed.
To help prevent DoS misuse, you can do the following:
Incorporate controls at the application level. Due to the number of variations possible, a default configuration is not feasible.
In your application you should:
404for all others.
Check the configuration of the default renderers, which can be a problem area.
In particular, the JSON renderer transverses the tree structure over multiple levels.
For example, the request:
could dump the whole repository in a JSON representation which can cause significant server problems. For this reason, Sling sets a limit on the number of maximum results. To limit the depth of the JSON rendering, set the value for the following:
JSON Max results (
in the configuration for the Apache Sling GET Servlet. When this limit is exceeded, the rendering is collapsed. The default value for Sling within AEM is
As a preventive measure, you should disable the other default renderers (HTML, plain text, XML). Again, by configuring the Apache Sling GET Servlet.
Do not disable the JSON renderer because it is required for the normal operation of AEM.
Use a firewall to filter access to your instance.
Mitigate Against DoS Caused by Using Form Selectors
This mitigation should be performed only on AEM environments that are not using Forms.
Because AEM does not provide out-of-the-box indexes for the
FormChooserServlet, using form selectors in queries can trigger a costly repository traversal, usually grinding the AEM instance to a halt. Form selectors can be detected by the presence of the *.form.* string in queries.
To mitigate this issue, you can do the following steps:
Go to the Web Console by pointing your browser to https://<serveraddress>:<serverport>/system/console/configMgr
Search for Day CQ WCM Form Chooser Servlet
After you click the entry, disable the Advanced Search Require in the following window.
Mitigate Against DoS Caused by Asset Download Servlet
The default asset download servlet allows authenticated users to issue arbitrarily large, concurrent, download requests to create ZIP files of assets. Creating large ZIP archives can overload the server and the network. To mitigate a potential Denial of Service (DoS) risk caused by this behavior,
AssetDownloadServlet OSGi component is disabled by default on Experience Manager publish instance. It is enabled on Experience Manager author instance by default.
If you do not need the download capability, disable the servlet on author and publish deployments. If your setup requires that the asset download capability is enabled, see this article for more information. Also, you can define a maximum download limit that your deployment can support.
Disable WebDAV on both the author and publish environments by stopping the appropriate OSGi bundles.
Connect to the Felix Management Console running on:
In the list of bundles, find the bundle named:
Apache Sling Simple WebDAV Access to repositories (org.apache.sling.jcr.webdav)
To stop this bundle, in the Actions column, click the stop button.
Again, in the list of bundles, find the bundle named:
Apache Sling DavEx Access to repositories (org.apache.sling.jcr.davex)
To stop this bundle, click the stop button.
A restart of AEM is not required.
It is important to protect your users by making sure that you do not expose any personally identifiable information in the repository users home path.
Since AEM 6.1, the way user (also known as authorizable) ID node names are stored is changed with a new implementation of the
AuthorizableNodeName interface. The new interface no longer exposes the user ID in the node name but generates a random name instead.
No configuration must be performed to enable it, because it is now the default way of generating authorizable IDs in AEM.
Although not recommended, you can disable it in case you need the old implementation for backward compatibility with your existing applications. To do so, you must do the following:
Go to the Web Console and remove the** org.apache.jackrabbit.oak.security.user.RandomAuthorizableNodeName** entry from property requiredServicePids in Apache Jackrabbit Oak SecurityProvider.
You can also find the Oak Security Provider by looking for the org.apache.jackrabbit.oak.security.internal.SecurityProviderRegistration PID in the OSGi configurations.
Delete the Apache Jackrabbit Oak Random Authorizable Node Name OSGi configuration from the Web Console.
For easier lookup, the PID for this configuration is org.apache.jackrabbit.oak.security.user.RandomAuthorizableNodeName.
For more information, see the Oak documentation on Authorizable Node Name Generation.
By default, AEM stores system metadata, such as
jcr:lastModifiedBy as node properties, next to regular content, in the repository. Depending on the configuration and the access control setup, in some cases this could lead to exposure of personally identifiable information (PII), for example, when such nodes are rendered as raw JSON or XML.
Like all repository data, these properties are mediated by the Oak authorization stack. Access to them should be restricted in accordance with the principle of least privilege.
To support this, Adobe provides a permission hardening package as a basis for customers to build upon. It works by installing a “deny” access control entry at the repository root, restricting anonymous access to commonly used system properties. The package is available for download here and can be installed on all supported versions of AEM.
To illustrate the changes, we can compare the node properties that can be viewed anonymously before installing the package:
with the ones viewable after installing the package, where
jcr:lastModifiedBy are not visible:
For more information see the package release notes.
To prevent clickjacking, Adobe recommends that you configure your webserver to provide the
X-FRAME-OPTIONS HTTP header set to
For more information on clickjacking, see the OWASP site.
Certain AEM features and authentication schemes require that you replicate your encryption keys across all AEM instances.
Before you do so, key replication is done differently between versions because the way keys are stored is different between 6.3 and older versions.
See below for more information.
Whereas in older versions the replication keys were stored in the repository, beginning with AEM 6.3 they are stored on the filesystem.
Therefore, to replicate your keys across instances, copy them from the source instance to the target instances’ location on the filesystem.
More specifically, you must do the following:
Access the AEM instance – typically an author instance – that contains the key material to copy;
Locate the com.adobe.granite.crypto.file bundle in the local file system. For example, under this path:
bundle.info file inside each folder identifies the bundle name.
Navigate to the data folder. For example:
Copy the HMAC and master files.
Then, go to the target instance you want to duplicate the HMAC key to, and navigate to the data folder. For example:
Paste the two files you previously copied.
Refresh the Crypto Bundle if the target instance is already running.
Repeat the above steps for all instances that you want to replicate the key to.
In AEM 6.2 and older versions, the keys are stored in the repository under the
The recommended way to securely replicate the keys across your instances is to only replicate this node. You can selectively replicate nodes via CRXDE Lite:
Adobe recommends that you perform a penetration test of your AEM infrastructure before going on production.
It is critical that new development are following the Security Best Practices to ensure that your AEM environment stays safe.