The remote host is missing an update to crawl announced via advisory DSA 432-1.

https://secure1.securityspace.com/smysecure/catid.html?in=DSA%20432-1

Steve Kemp from the GNU/Linux audit project discovered a problem in crawl, another console based dungeon exploration game, in the vein of nethack and rogue. The program uses several environment variables as inputs but doesn't apply a size check before copying one of them into a fixed size buffer. For the stable distribution (woody) this problem has been fixed in version 4.0.0beta23-2woody1. For the unstable distribution (sid) this problem has been fixed in version 4.0.0beta26-4. We recommend that you upgrade your crawl package.