Subversion versions up to and including 1.0.5 have a bug in
mod_authz_svn that allows users with write access to read
portions of the repository that they do not have read access
to.  Subversion 1.0.6 and newer (including 1.1.0-rc1) are not
vulnerable to this issue.

Details:
========

mod_authz_svn would allow a user to copy portions of a repo to which
they did not have read permissions to portions that they did have 
read permissions on, thereby evading the read restrictions.

Severity:
=========

This is a low risk issue.  Only sites running mod_authz_svn (an
Apache module) that are trying to restrict some of their users
with write access to a repo from reading part of that repo are
vulnerable.

Most installations will not fall into this category.
Additionally, any attempt to use such a vulnerability will be
apparent as the copy will be versioned.  Plus, it's doubtful
any site would permit public write access to its repository
so this issue should not be accessible by unauthenticated users.

This vulnerability does not affect users running svnserve.

Workarounds:
============

* Disable DAV and use svnserve.

* Separate content into different repos.

* Disable the COPY method via Apache configuration.  Note this will
  disallow all copies.

Recommendations:
================

We recommend all users upgrade to 1.0.6 or 1.1.0-rc1.