The js::jit::AssemblerX86Shared::lock_addl function in the JavaScript implementation in Mozilla Firefox before 40.0 and Firefox ESR 38.x before 38.2 allows remote attackers to cause a denial of service (application crash) by leveraging the use of shared memory and accessing (1) an Atomics object or (2) a SharedArrayBuffer object.
Exploitability
AV:NAC:LAu:NImpact
C:NI:NA:P5/AV:N/AC:L/Au:N/C:N/I:N/A:P