The remote host is missing an update to gnupg2 announced via advisory DSA 1115-1. Evgeny Legerov discovered that gnupg, the GNU privacy guard, a free PGP replacement contains an integer overflow that can cause a segmentation fault and possibly overwrite memory via a large user ID strings.
For the stable distribution (sarge) this problem has been fixed in version 1.4.1-1.sarge4 of GnuPG and in version 1.9.15-6sarge1 of GnuPG2. For the unstable distribution (sid) this problem has been fixed in version 1.4.3-2 of GnuPG, a fix for GnuPG2 is pending. We recommend that you upgrade your gnupg package. https://secure1.securityspace.com/smysecure/catid.html?in=DSA%201115-1