Unauthorized modification of displayed content in IS-Media, SAP security note 1496148

SAP security note 1496148, “Unauthorized modification of displayed content in IS-Media”, is a note. Below are the symptom and SAP recommended solution.

Description

Symptom

The IS-Media could be abused by a malicious user, who could modify displayed application content without authorization and potentially obtain authentication information from other legitimate users.

Solution

After you implement the corrections, the data that is output is checked for invalid values on all pages of the relevant applications.

If you are using one of the applications that are corrected with this note and you are using a release with a Support Package level that is not corrected by this note, then implement the following manual corrections for the views and pages with flow logic of the BSPs:

• Add the parameter forceEncode="html" to the <%page> directive.
• Add the parameter forceEncode="enabled" to the tag <htmlb:content> (not for the pages default.htm or default_old.htm of BSP ISMCAMPAIGNPICK).

Reason and prerequisites

IS-Media does not sufficiently encode issues, resulting in a reflected cross-site scripting issue. A reflected cross-site scripting attack can be used to non-permanently deface or modify displayed content from a web site.

Reflected cross-site scripting can be used to steal another user’s authentication information, such as data relating to their current session. An attacker who gains access to this data could use it to impersonate the user and access all information with the same rights as the target user.

If an administrator is impersonated, the application’s security could be fully compromised.

References