Security researcher Holger Fuhrmannek and Mozilla security engineer Tyson Smith reported a number of security vulnerabilities in the Graphite 2 library affecting version 1.3.5.
The issue reported by Holger Fuhrmannek is a mechanism to induce stack corruption with a malicious graphite font. This leads to a potentially exploitable crash when the font is loaded.
Tyson Smith used the Address Sanitizer tool in concert with a custom software fuzzer to find a series of uninitialized memory, out-of-bounds read, and out-of-bounds write errors when working with fuzzed graphite fonts.
To address these security vulnerabilities, Firefox 45 and Firefox ESR 38.7 have been updated to Graphite 2 version 1.3.6.