Orca Browser 1.2 build 5 does not properly block data: URIs in Refresh and Location headers in HTTP responses, which allows remote attackers to conduct cross-site scripting (XSS) attacks via vectors related to (1) injecting a Refresh header that contains JavaScript sequences in a data:text/html URI, (2) entering a data:text/html URI with JavaScript sequences when specifying the content of a Refresh header, (3) injecting a Location header that contains JavaScript sequences in a data:text/html URI, or (4) entering a data:text/html URI with JavaScript sequences when specifying the content of a Location header; and does not properly handle javascript: URIs in HTML links within 302 error documents sent from web servers, which allows user-assisted remote attackers to conduct cross-site scripting (XSS) attacks via vectors related to (5) injecting a Location HTTP response header or (6) specifying the content of a Location HTTP response header.