svnserve is vulnerable to a local privilege escalation vulnerability via symlink attack.

Subversion Project reports:

svnserve takes a --pid-file option which creates a file containing the
process id it is running as. It does not take steps to ensure that the file
it has been directed at is not a symlink. If the pid file is in a directory
writeable by unprivileged users, the destination could be replaced by a
symlink allowing for privilege escalation. svnserve does not create a pid
file by default.
All versions are only vulnerable when the --pid-file=ARG option is used.