phlex makes Cross-site Scripting (XSS) possible due to improper sanitisation of `href` attributes on `<a>` tags

phlex is an open source framework for building object-oriented views in Ruby. There is a potential cross-site scripting (XSS) vulnerability that can be exploited via maliciously crafted user data. The filter to detect and prevent the use of the `javascript:` URL scheme in the `href` attribute of an `<a>` tag could be bypassed with tab `\t` or newline `\n` characters between the characters of the protocol, e.g. `java\tscript:`. This vulnerability is fixed in 1.10.1, 1.9.2, 1.8.3, 1.7.2, 1.6.3, 1.5.3, and 1.4.2. Configuring a Content Security Policy that does not allow `unsafe-inline` would effectively prevent this vulnerability from being exploited.