The remote host is missing an update to zgv announced via advisory DSA 1037-1. Andrea Barisani discovered that zgv, an svgalib graphics viewer, attempts to decode JPEG images within the CMYK/YCCK colour space incorrectly, which could lead to the execution of arbitrary code. For the old stable distribution (woody) this problem has been fixed in version 5.5-3woody3.
For the stable distribution (sarge) this problem has been fixed in version 5.7-1.4. For the unstable distribution (sid) this problem has been fixed soon. We recommend that you upgrade your zgv package. https://secure1.securityspace.com/smysecure/catid.html?in=DSA%201037-1