Google security researcher Michal Zalewski reported an issue where the browser displayed the content of a proxy's 407 response if a user canceled the proxy's authentication prompt. In this circumstance, the addressbar will continue to show the requested site's address, including HTTPS addresses that appear to be secure. This spoofing of addresses can be used for phishing attacks by fooling users into entering credentials, for example. In general these flaws cannot be exploited through email in the Thunderbird and SeaMonkey products because scripting is disabled, but are potentially a risk in browser or browser-like contexts in those products. External Reference: http://www.mozilla.org/security/announce/2013/mfsa2013-27.html Acknowledgements: Red Hat would like to thank the Mozilla project for reporting this issue. Upstream acknowledges Michal Zalewski as the original reporter.
This issue has been addressed in following products: Red Hat Enterprise Linux 5 Red Hat Enterprise Linux 6 Via RHSA-2013:0272 https://rhn.redhat.com/errata/RHSA-2013-0272.html
This issue has been addressed in following products: Red Hat Enterprise Linux 5 Red Hat Enterprise Linux 6 Via RHSA-2013:0271 https://rhn.redhat.com/errata/RHSA-2013-0271.html