> On Dec 29, 2022, at 11:43 AM, Alan Coopersmith = wrote: Another solution is to escape bytes that might cause trouble in this = field, e.g., using %xx hexadecimal. So space would be %20, ")" would be %41, control characters 1-31 would = be %01 to %1f, and (of course) "%" would be encoded as %25. Basically, URL-encode / Percent-encode them. See: = https://en.wikipedia.org/wiki/Percent-encoding Technically this would be a userspace change, but only in cases where = the system would probably have done the wrong thing previously. It's okay if we = break *attacker* workflows as long as we don't break others'. An advantage of URL encoding is that, like JSON, it's a well-known format. I might do something different if = this was a new system, but that seems like the least-impact approach while eliminating the = problem. --- David A .Wheeler