High Quality Content by WIKIPEDIA articles! Man-in-the-browser (MITB, MitB, MIB, MiB), a form of Internet threat related to man-in-the-middle (MITM), is a proxy Trojan horse that infects a web browser by taking the advantage of vulnerabilities in browser security to modify web pages, modify transaction content or insert additional transactions, all in a completely covert fashion invisible to both the user and host web application. A MitB attack will be successful irrespective of whether security mechanisms such as SSL/PKI and/or two or three-factor Authentication solutions are in place. A MitB attack may be countered by utilising out-of-band transaction verification, although SMS verification can be defeated by man-in-the-mobile (MitMo) malware infection on the mobile phone. Trojans may be detected and removed by antivirus software with a 23% success rate against Zeus in 2009, and still low rates in 2011. The 2011 report concluded that additional measures on top of antivirus were needed. A related, more simple attack is the boy-in-the-browser (BitB, BITB). The majority of financial service professionals in a survey considered MitB to be the greatest threat to online banking. For online banking, using portable applications or using alternatives to Microsoft Windows like Mac OS X, Linux or mobile OSes may be the safest, especially when run from non-installed media.