Invalid Memory Access in the fxProxyGetter function in moddable/xs/sources/xsProxy.c in Moddable SDK before OS200908 causes a denial of service (SEGV).

Invalid Memory Access in fxUTF8Decode at moddable/xs/sources/xsCommon.c:916 in Moddable SDK before OS200908 causes a denial of service (SEGV).

Null Pointer Dereference. in xObjectBindingFromExpression at moddable/xs/sources/xsSyntaxical.c:3419 in Moddable SDK before OS200908 causes a denial of service (SEGV).

Heap buffer overflow at moddable/xs/sources/xsDebug.c in Moddable SDK before before 20200903. The top stack frame is only partially initialized because the stack overflowed while creating the frame. This leads to a crash in the code sending the stack frame to the debugger.

In XS 9.0.0 in Moddable SDK OS180329, there is a heap-based buffer overflow in fxBeginHost in xsAPI.c when called from fxRunDefine in xsRun.c, as demonstrated by crafted JavaScript code to xst.