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Firefox Privacy Notice

Mozilla Foundation Security Advisory 2016-04

Firefox allows for control characters to be set in cookie names

Announced
January 26, 2016
Reporter
musicDespiteEverything, Nicholas Hurley
Impact
Moderate
Products
Firefox
Fixed in
  • Firefox 44

Description

Security researcher musicDespiteEverything previously reported an issue where illegal control characters were stored in as cookie values in violation of RFC6265. While fixing this issue, Mozilla developer Nicholas Hurley realized that the same issue applied to the names of cookies. These characters have now been disallowed in cookie names. This issue could result in incorrect cookie handling by web servers.

References