TEC Workbook - IBM

IBM Software
● MegaTags – Otherwise valid XML messages containing excessively long element names,
or an excessive number of tags. This attack may also lead to buffer overruns.
● Coercive parsing – XML messages specially constructed to be difficult to parse, resulting
in excessive resource consumption in the target machine.
● Public key DoS – Utilizing the asymmetric nature of public key operations to force
resource exhaustion on the recipient by transmitting a message with a large number of
long-key-length, computationally expensive digital signatures.
Multiple message XDoS (MMXDoS) attacks may have the following characteristics:
● XML flood – sending thousands of otherwise benign messages per second to tie up a
Web service. This attack can be combined with Replay attack to bypass authentication,
and with Single message XDoS to increase its impact.
● Resource hijack – sending messages that lock or reserve resources on the target server
as part of a never-completed transaction.
__1. At the top of the Multi-Protocol Gateway configuration form is a set of tabs. At the right and left
side of the tabs are arrow images. Moving the cursor over the arrow (without clicking) will cause
the tabs to shift left or right. Move the mouse over the right arrow until the XML Threat Protection
tab is visible.
__2. Click on the XML Threat Protection tab.
__3. In the Single Message XML Denial of Service section, click the on radio button for Gateway
parser limits.
Notice that the XDoS protection is highly customizable.
__4. Click the off button for Gateway parser limits.
__5. In the Multiple Message XML Denial of Service section, click the on radio button for Enable
MMXDoS Protection.
__6. Click the off button for Enable MMXDos Protection.
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