The ssh_gssapi_parse_ename function in gss-serv.c in OpenSSH 5.8 and earlier, when gssapi-with-mic authentication is enabled, allows remote authenticated users to cause a denial of service (memory consumption) via a large value in a certain length field. NOTE: there may be limited scenarios in which this issue is relevant.
https://euvd.enisa.europa.eu/vulnerability/EUVD-2011-4905
http://site.pi3.com.pl/adv/ssh_1.txt