Most web applications use a session identifier to uniquely identify users, which is typically stored in a cookie and transmitted transparently between the server and the web browser.


When the value of the attribute is set to either true or UseUri, the application does not use cookies regardless of whether the browser or device supports cookies. When the value of the attribute is set to either AutoDetect or UseDeviceProfile, the cookies are not used depending on the configuration of the requesting browser or device.

Applications that do not store session identifiers in cookies sometimes transmit them as an HTTP request parameter or as part of the URL. Accepting session identifiers specified in URLs makes it easy for attackers to perform Session Fixation attacks.

Placing session identifiers in URLs can also increase the chances of successful Session Hijacking attacks against the application. Session Hijacking occurs when an attacker takes control of a victim's active session or session identifier. It is common practice for web servers, application servers, and web proxies to store requested URLs. If session identifiers are included in URLs, they are also logged. Increasing the number of places session identifiers are viewed and stored increases the chances they will be compromised by an attacker.

ASP.NET applications can be configured to output trace debugging information. Trace output contains details about the request made to the current page, header information, methods, and controls used on the page and the active session state. Attackers may leverage the additional information they gain from trace output to mount attacks targeted on the framework, database, or other resources used by the application.

Trace information is enabled at the page level by setting the Trace attribute of the <page> directive to true or on the application level by adding a trace element in the web.config file and setting its enabled attribute to true.

The use of impersonated credentials allows an ASP.NET application to run with either the privileges of the client on whose behalf it is executing or with arbitrary privileges granted in its configuration.

ASP.NET applications can store user name and password pairs in <credentials> elements in the web.config file for an ASP.NET application, which supports plain text, MD5 and SHA1 password formats.

Passwords stored in plain text or using a weak encryption algorithm are accessible to anyone with the access to the application's configuration files. This may include the machine where the application is hosted or the source code repository where the application lives.

Example 1: The following web.config entry incorrectly stores its passwords in plain text.

<configuration>
  <system.web>
    <authentication>
      <forms protection="All">
	   <credentials passwordFormat="Clear">
   		<user name="user1" password="my_password"/>
		<user name="user2" password="my_password1"/>
        </credentials>
    	 </forms>
    </authentication>
  </system.web>
</configuration>

ASP.NET supports credential passwords stored in three formats, specified by the passwordFormat attribute of the configuration/system.web/authentication/forms/credentials element. The possible values for this attribute are:

Clear - indicates that the password is stored in plain text (least secure)
MD5 - indicates that the password's MD5 hash is stored
SHA1 - indicates that the password's SHA1 hash is stored (most secure)

While an MD5 hash is more secure than plain text, researchers have found brute-force attacks against the MD5 hashing algorithm. At this time, a SHA1 hash still provides reasonable protection against such attacks.

Customer-managed keys are not used to encrypt data at rest.

By default, AWS uses AWS-managed keys to encrypt data at rest if encryption is enabled. Customer-managed keys enable organizations to use cryptographic keys of their choice to encrypt data. This gives organizations better control over and logging of encryption processes.

As such, customer-managed keys are often part of the solution to address requirements that include but are not limited to:
- Audit logs for sensitive data access
- Data residency
- Replacing, disabling, or destroying keys

Note that keys with the format aws/service-name are reserved for AWS-managed keys.

Loose access configurations can expose systems and broaden an organization's attack surface. Services open to interaction with the public are typically subjected to near-continuous scanning and probing by malicious entities.

This is especially problematic when a zero-day exploit for an exposed service is discovered and published, such as Heartbleed. Attackers can actively pursue and search for unpatched and exposed systems to exploit.

Uncontrolled access to critical or sensitive resources can significantly impact an organization in various ways, including disclosure of or tampering with critical data.