This could be due to a bug that has just been fixed this week in viewer-development and was backported in
today's releases.
I can't however confirm since I wiped out the secondlife.pdb file (debug symbols) for v1.26.4.47 when I built v1.26.4.48 earlier today, making your crash-dump undecipherable... Please, try v1.26.4.48 and let me know (with the corresponding logs and crash dump) if it happens again with it.