Zeyouliu

**Name of the Vulnerable Software and Affected Versions** Expat versions prior to 2.8.4 **Description** An out-of-bounds read allows attackers to trigger memory corruption when processing XML using external entity parsers created via the `XML ExternalEntityParserCreate()` function. A struct size mismatch between `ELEMENT TYPE` members causes the `storeAtts()` function to read the `attIndex` member beyond allocated memory boundaries. This leads to a failure to normalize whitespace in non-CDATA attributes or a wild pointer dereference, which results in a segmentation fault (a crash occurring when a program attempts to access a memory location it is not allowed to access). **Recommendations** Update Expat to version 2.8.4 or later. As a temporary mitigation, restrict the use of the `XML ExternalEntityParserCreate()` function.