Stored XSS in ka9q_ubersdr chat message rendering

madpsy ka9q_ubersdr before 0.1.58 has a stored cross-site scripting (XSS) vulnerability in the chat message rendering functionality. User-controlled URLs in chat messages were insufficiently neutralized before being converted into HTML links. Quotation characters could break out of the generated href attribute and introduce attacker-controlled HTML attributes, allowing arbitrary JavaScript to execute in the browser of another user when the stored chat message was rendered. No click on the malicious link was required.