YOP Poll < 6.2.8 - Unauthenticated Stored Cross-Site Scripting

Description

In the plugin, when a poll is created with the options "Allow other answers", "Display other answers in the result list" and "Show results", it can lead to Stored Cross-Site Scripting issues as the 'Other' answer is not sanitised before being output in the page. The execution of the XSS payload depends on the 'Show results' option selected, which could be before or after sending the vote for example.