Bug 163

Summary:	session handling vulnerability
Product:	Sudo	Reporter:	Mravik Attila <evik>
Component:	Sudo	Assignee:	Todd C. Miller <Todd.Miller>
Status:	RESOLVED INVALID
Severity:	security
Priority:	normal
Version:	1.6.8
Hardware:	PC
OS:	Linux

Description Mravik Attila 2004-12-26 09:21:21 MST

Sudo asks a password for first use and then stores it for a "session". (I think
ist about 5 minutes or so.) I found that this session is binded to user but not
to any terminal. Meaning that if I login at tty1 and use sudo, "unlocking" it
with my password, a malicious user who got a user shell could use sudo without
password.
(Well at least one more security hole is required for gaining a user shell, but
this session handling could elevate the gained privileges to (semi) root
privileges.)
I use Debian Linux 3.1, and tested only on this particular OS.

Comment 1 Todd C. Miller 2004-12-29 20:05:11 MST

Sudo supports per-tty ticket files via the tty_tickets sudoers option; see the sudoers manual for more 
info.  Note, however that unless you explicitly kill the ticket (sudo -k) when you logout, the same user 
logging in on the the same tty within 5 minutes will not be prompted for a password.