The remote host is missing an update to xbl announced via advisory DSA 327-1.

https://secure1.securityspace.com/smysecure/catid.html?in=DSA%20327-1

Steve Kemp discovered several buffer overflows in xbl, a game, which can be triggered by long command line arguments. This vulnerability could be exploited by a local attacker to gain gid 'games'. For the stable distribution (woody) this problem has been fixed in version 1.0k-3woody1. For the old stable distribution (potato) this problem has been fixed in version 1.0i-7potato1. For the unstable distribution (sid) this problem is fixed in version 1.0k-5. We recommend that you update your xbl package.