Debian DSA-2368-1 : lighttpd - multiple vulnerabilities (BEAST)


Several vulnerabilities have been discovered in lighttpd, a small and fast webserver with minimal memory footprint. - CVE-2011-4362 Xi Wang discovered that the base64 decoding routine which is used to decode user input during an HTTP authentication, suffers of a signedness issue when processing user input. As a result it is possible to force lighttpd to perform an out-of-bounds read which results in Denial of Service conditions. - CVE-2011-3389 When using CBC ciphers on an SSL enabled virtual host to communicate with certain client, a so called 'BEAST' attack allows man-in-the-middle attackers to obtain plaintext HTTP traffic via a blockwise chosen-boundary attack (BCBA) on an HTTPS session. Technically this is no lighttpd vulnerability. However, lighttpd offers a workaround to mitigate this problem by providing a possibility to disable CBC ciphers. This updates includes this option by default. System administrators are advised to read the NEWS file of this update (as this may break older clients).