Multiple vulnerabilities are addressed in an update of the Opera operating system, though its makers are keeping the lid on one because it might also affect other so-far unpatched programs.

Version 9.5.2 of the Windows version of the software fixes seven vulnerabilities, and advisories are available on six of them, reports The Register.

Computerworld reports it said of the seventh:

Fixed an issue that could allow cross-site scripting, as reported by Chris Weber of Casaba Security; details will be disclosed at a later date.

The bugs, including five in the Mac edition and six in the Linux browser, range from "extremely severe" to "not severe" in the company's five-level ranking system.