A vulnerability has been discovered in Sympa web interface
by which attacker can execute arbitrary code with root privileges.
Sympa uses two sorts of setuid wrappers:
- FastCGI wrappers
- newaliases wrapper
The FastCGI wrappers wwsympa-wrapper.fcgi and
sympa_soap_server-wrapper.fcgi were used to make the web
interface running under privileges of a dedicated user.
The newaliases wrapper (sympa_newaliases-wrapper) allows
Sympa to update the alias database with root privileges.
Since these setuid wrappers did not clear environment variables,
if environment variables like PERL5LIB were injected,
forged code might be loaded and executed under privileges of setuid-ed
users.