An out-of-bounds read during the processing of glyph widths during text layout. This results in a potentially exploitable crash and could allow an attacker to read otherwise inaccessible memory. This vulnerability affects Thunderbird < 52.1, Firefox ESR < 45.9, Firefox ESR < 52.1, and Firefox < 53.
535345.952.145.952.1Exploitability
AV:NAC:LPR:NUI:NScope
S:UImpact
C:HI:NA:H9.1/CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:H