The remote host is missing an update to axel announced via advisory DSA 706-1.

https://secure1.securityspace.com/smysecure/catid.html?in=DSA%20706-1

Ulf Härnhammar from the Debian Security Audit Project discovered a buffer overflow in axel, a light download accellerator. When reading remote input the program did not check if a part of the input can overflow a buffer and maybe trigger the execution of arbitrary code. For the stable distribution (woody) this problem has been fixed in version 1.0a-1woody1. For the unstable distribution (sid) this problem has been fixed in version 1.0b-1. We recommend that you upgrade your axel package.