It was discovered that php-json-ext, a JSON serialiser for PHP, is prone to a denial of service attack, when receiving a malformed string via the json_decode function. For the oldstable distribution , this problem has been fixed in version 1.2.1-3.2+etch1. The stable distribution does not contain a separate php-json-ext package, but includes it in the php5 packages, which will be fixed soon. The testing distribution and the unstable distribution do not contain a separate php-json-ext package, but include it in the php5 packages. We recommend that you upgrade your php-json-ext packages.