Xerces-C++ is a validating XML parser written in a portable subset of C++.
Frank Rast reported that the XML parser in Xerces-C++ does not correctly handle an XML schema definition with a large maxOccurs value, which triggers excessive memory consumption during the validation of an XML file.
A remote attacker could entice a user or automated system to validate an XML file using a specially crafted XML schema file, leading to a Denial of Service (stack consumption and crash).
There is no known workaround at this time.
All Xerces-C++ users should upgrade to the latest version:
# emerge --sync # emerge --ask --oneshot --verbose ">=dev-libs/xerces-c-3.0.0-r1"