The hash_buffer function in schnorr.c in OpenSSH through 6.4, when Makefile.inc is modified to enable the J-PAKE protocol, does not initialize certain data structures, which might allow remote attackers to cause a denial of service (memory corruption) or have unspecified other impact via vectors that trigger an error condition.
http://marc.info/?l=bugtraq&m=141576985122836&w=2
http://marc.info/?l=bugtraq&m=144050155601375&w=2
http://openwall.com/lists/oss-security/2014/01/29/10
http://openwall.com/lists/oss-security/2014/01/29/2
http://secunia.com/advisories/60184
http://www.openbsd.org/cgi-bin/cvsweb/src/usr.bin/ssh/Attic/schnorr.c.diff?r1=1.9;r2=1.10;f=h
http://www.openbsd.org/cgi-bin/cvsweb/src/usr.bin/ssh/schnorr.c#rev1.10
http://www.securityfocus.com/bid/65230