7.5 - USN-147-1

A security issue affects the following Ubuntu releases:

Ubuntu 4.10 (Warty Warthog) Ubuntu 5.04 (Hoary Hedgehog)

The following packages are affected:

libapache2-mod-php4 php4-pear

The problem can be corrected by upgrading the affected package to version 4:4.3.8-3ubuntu7.9 (for Ubuntu 4.10), or 4:4.3.10-10ubuntu3.1 (for Ubuntu 5.04). In general, a standard system upgrade is sufficient to effect the necessary changes.

Details follow:

A remote code execution vulnerability has been discovered in the XMLRPC module of the PEAR (PHP Extension and Application Repository) extension of PHP. By sending specially crafted XMLRPC requests to an affected web server, a remote attacker could exploit this to execute arbitrary code with the web server's privileges.

In Ubuntu 5.04 (Hoary Hedgehog), the PEAR extension is unsupported (it is contained in the php4-universe package which is part of universe). However, since this is a highly critical vulnerability, that package was fixed as well.

Please note that many applications contain a copy of the affected XMLRPC code, which must be fixed separately. The following packages may also be affected, but are unsupported in Ubuntu:

- drupal
- wordpress
- phpwiki
- horde3
- ewiki
- egroupware
- phpgroupware

These packages might be fixed by the community later.

The following common third party applications are affected as well, but not packaged for Ubuntu:

- Serendipity
- Postnuke
- tikiwiki
- phpwebsite

If you run any affected software, please upgrade them as soon as possible to protect your server.