The remote host is missing an update to php5 announced via advisory USN-761-2.

The problem can be corrected by upgrading your system to the following package versions: Ubuntu 9.04: libapache2-mod-php5 5.2.6.dfsg.1-3ubuntu4.1 php5-cgi 5.2.6.dfsg.1-3ubuntu4.1 php5-cli 5.2.6.dfsg.1-3ubuntu4.1 In general, a standard system upgrade is sufficient to effect the necessary changes. https://secure1.securityspace.com/smysecure/catid.html?in=USN-761-2

USN-761-1 fixed vulnerabilities in PHP. This update provides the corresponding updates for Ubuntu 9.04. Original advisory details: It was discovered that PHP did not sanitize certain error messages when display_errors is enabled, which could result in browsers becoming vulnerable to cross-site scripting attacks when processing the output. With cross-site scripting vulnerabilities, if a user were tricked into viewing server output during a crafted server request, a remote attacker could exploit this to modify the contents, or steal confidential data (such as passwords), within the same domain. (CVE-2008-5814) It was discovered that PHP did not properly handle certain malformed strings when being parsed by the json_decode function. A remote attacker could exploit this flaw and cause the PHP server to crash, resulting in a denial of service. This issue only affected Ubuntu 8.04 and 8.10. (CVE-2009-1271)