The remote host is missing an update to the system as announced in the referenced advisory.
Update your system with the appropriate patches or software upgrades. http://www.apache.org/dist/apr/Announcement0.9.html http://www.vuxml.org/freebsd/38560d79-0e42-11e1-902b-20cf30e32f6d.html
The following package is affected: apr0 CVE-2011-0419 Stack consumption vulnerability in the fnmatch implementation in apr_fnmatch.c in the Apache Portable Runtime (APR) library before 1.4.3 and the Apache HTTP Server before 2.2.18, and in fnmatch.c in libc in NetBSD 5.1, OpenBSD 4.8, FreeBSD, Apple Mac OS X 10.6, Oracle Solaris 10, and Android, allows context-dependent attackers to cause a denial of service (CPU and memory consumption) via *? sequences in the first argument, as demonstrated by attacks against mod_autoindex in httpd.