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Firefox Privacy Notice

Mozilla Foundation Security Advisory 2015-137

Firefox allows for control characters to be set in cookies

Announced
December 15, 2015
Reporter
musicDespiteEverything
Impact
Moderate
Products
Firefox
Fixed in
  • Firefox 43

Description

Security researcher musicDespiteEverything reported an issue when ASCII code 11 for vertical tab is stored in a cookie in violation of RFC6265. This may result in incorrect cookie handling by servers, resulting in the potential ability to set cookie values and read cookie data from users in concert with some web servers if the vertical tab character is mishandled during parsing.

References