An issue was discovered in the DBI module before 1.643 for Perl. The hv_fetch() documentation requires checking for NULL and the code does that. But, shortly thereafter, it calls SvOK(profile), causing a NULL pointer dereference.
An untrusted pointer dereference flaw was found in Perl-DBI < 1.643. A local attacker who is able to manipulate calls to dbd_db_login6_sv() could cause memory corruption, affecting the service's availability.