It appears that the Mozilla folks are about to release Firefox 1.5.0.6 (don't rush out and try to download it yet, the main Firefox page doesn't show it yet and for most of us, the automatic check will alert us to its availability).  No details at the moment on what this one fixes, but coming so quickly on the heals of 1.5.0.5, I would imagine that there must be some security implications.  We'll update this story as soon as the Release Notes are available.  And thank you to our ever faithful reader, Juha-Matti for alerting us to this.

Update 20:27 UTC:  If Bugzilla can be belived, all this update does is fix an issue with "mms://" and related multi-media URLs that have been broken in 1.5.0.5. Apparently, not all updates rushed out while a Blackhat conference is going on have a sinister reason :-).

Update 03:48 UTC: Firefox 1.5.0.6 is formally released.  The release notes confirm it fixes an issue with Windows Media.