Mozilla Foundation Security Advisory 2008-02

Multiple file input focus stealing vulnerabilities

February 7, 2008
hong, Gregory Fleischer
Firefox, SeaMonkey
Fixed in
  • Firefox
  • SeaMonkey 1.1.8


Security researchers hong and Gregory Fleischer each reported a variant on earlier reported bugs regarding focus shifting in file input controls. Their variants used file input controls nested inside <label> tags to take advantage of automatic focus shifting into the file input field noted on the Hacker WebZine. As with the earlier reported issues this issue could be used to force a user to upload arbitrary files assuming the attacker knows the full path and name of the file.

These bugs are variations on earlier problems reported by Charles McAuley and Michal Zalewski which were fixed in Firefox, as well as an issue reported by hong which was fixed in Firefox

Gregory Fleischer also submitted several other variations of the same problem.