** DISPUTED **  Mozilla Firefox 1.0.7 and 1.5.0.1 allows remote attackers to cause a denial of service (crash) via an HTML tag with a large number of script action handlers such as onload and onmouseover, which triggers the crash when the user views the page source.  NOTE: Red Hat has disputed this issue, suggesting that "It is likely the reporter was running the IE Tab extension," and Mozilla also confirmed that this is not an issue in Firefox itself.