The txXPathNodeUtils::getXSLTId function in txMozillaXPathTreeWalker.cpp and txStandaloneXPathTreeWalker.cpp in Mozilla Firefox before 3.5.19, 3.6.x before 3.6.17, and 4.x before 4.0.1, and SeaMonkey before 2.0.14, allows remote attackers to obtain potentially sensitive information about heap memory addresses via an XML document containing a call to the XSLT generate-id XPath function.