I can confirm this behavior.
Works with get (get /tmp/\[test\]/moo) and even with ls from outside the
directory (ls /tmp/\[test\]). Just not when you cd to it.
** Changed in: openssh (Ubuntu)
Importance: Undecided => Low
** Changed in: openssh (Ubuntu)
Status: New => Confirmed
** Summ
** Attachment added: "Dependencies.txt"
http://launchpadlibrarian.net/39961002/Dependencies.txt
** Attachment added: "XsessionErrors.txt"
http://launchpadlibrarian.net/39961003/XsessionErrors.txt
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Can't sftp to directories with brackets in the name.
https://bugs.launchpad.net/bugs/53071
