Please see my previous comment on one of your segmentation faults for which you provided a dump that wasn’t from a segmentation fault: Asterisk Segmentation fault after call pickup - #2 by david551
Also note that version 13 will not have bugs fixed as it is now in security fixes only status, so please provide dumps from a currently supported version (with, of couse symbol tables from an unoptimised build).
Again this looks like memory corruption which may have happened some time before abort() was called, although this time it is in Dial() rather than in conference processing.