Launchpad.net

CVE 2017-5454

A mechanism to bypass file system access protections in the sandbox to use the file picker to access different files than those selected in the file picker through the use of relative paths. This allows for read only access to the local file system. This vulnerability affects Thunderbird < 52.1, Firefox ESR < 52.1, and Firefox < 53.

See the CVE page on Mitre.org for more details.