KB234507: "java.security.InvalidKeyException: Invalid AES key length: 20 bytes" error is logged and blank page is displayed using MicroStrategy Web Universal 9.3.x and 9.4.x on Weblogic.

SYMPTOM:
When attempting to login, users encounter a blank page. The following error message is logged in the web server logs:

<message>Invalid AES key length: 20 bytes (java.security.InvalidKeyException)</message>
 
  <exception>java.security.InvalidKeyException: Invalid AES key length: 20 bytes
	at com.sun.crypto.provider.AESCipher.engineGetKeySize​(DashoA13*..)
	at javax.crypto.Cipher.b(DashoA13*..)
	at javax.crypto.Cipher.a(DashoA13*..)
	at javax.crypto.Cipher.a(DashoA13*..)
	at javax.crypto.Cipher.a(DashoA13*..)
	at javax.crypto.Cipher.init(DashoA13*..)
	a​t javax.crypto.Cipher.init(DashoA13*..)
	a​t com.Strategy.utils.crypto.CryptoCipher1.encry​pt(Unknown Source)
	at com.Strategy.utils.crypto.CryptoSessionKey.en​crypt(Unknown Source)
	at com.Strategy.utils.crypto.CryptoSessionKey.en​crypt(Unknown Source)
	at com.Strategy.webapi.CDSSXMLEncryptor.Encrypt(​Unknown Source)
	at com.Strategy.web.objects.WebSessionInfoImpl.s​aveState(Unknown Source)
	at com.Strategy.web.app.beans.WebAppSessionManag​erImpl$LoginFirstContainer.saveState(Unknown Source)
	at com.Strategy.web.app.beans.WebAppSessionManag​erImpl.saveState(Unknown Source)
	at com.Strategy.utils.serialization.AbstractPers​istable.saveState(Unknown Source)
	at com.Strategy.utils.serialization.AbstractPers​istable.saveState(Unknown Source)
	at com.Strategy.web.controller.ControllerHelper.​saveSessionManager(Unknown Source)
	at com.Strategy.web.controller.GenericWebAppCont​roller.processRequest(Unknown Source)
	at com.Strategy.web.servlets.MainServlet.doGet(U​nknown Source)
	at javax.servlet.http.HttpServlet.service(HttpServlet​.java:707)
	at javax.servlet.http.HttpServlet.service(HttpServlet​.java:821)
	at

This issue occurs on environments having SSL encryption enabled and is usually reproduced on Oracle WebLogic application servers. In some cases, users encounter a blank page instead of being able to proceed to login. This issue occurs sporadically and can be temporarily solved with a restart of the web application server.
 
CAUSE:
This is a known limitation with Strategy Web 9.3.x and 9.4.x.
 
ACTION:
This limitation has been addressed with Strategy Web 9.4.1 Hotfix 6. Perform an upgrade of your environment in order to benefit from the fix.
 
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The internal reference to this issue is 946389.