Re: concurrent logins
Robin Wood <[email protected]> Wed, 19 Nov 2014 14:19:20 +0000
| Newsgroups | gmane.comp.security.web-applications |
|---|---|
| Message-ID | <CALmccy779OV4QcvkD13yC=-cOEhuDq2WZOuOP-to5z0LQwzsEA@mail.gmail.com> |
That is my number 3 but giving a warning when logging them out. Could still result in a DoS and you'd have to either write very good copy on the warning or train users what to do when that happens as I reckon most would just click OK and then log back in again. Robin On 19 November 2014 14:14, Rogan Dawes <[email protected]> wrote: > Think you missed: > > 7. Log the new session in, warn that another session was active, terminate > the old session. > > Seems to have all the desired properties. > > o Can't deny access to the account to someone with legit credentials. > o Prevent concurrent sessions > o Inform of concurrent sessions > o If the attacker logs in second, the legit user is informed that another > session was created, and that is the reason they were kicked out. This > should be an alarm bell, if they had not tried to authenticate at the time. > > Rogan > > On 19 Nov 2014 12:30, "Robin Wood" <[email protected]> wrote: >> >> What are peoples opinions on allowing concurrent logins to web apps? I >> suppose it depends on what the app is used for - forum, admin suite >> etc - but do the protections from it add more problems that allowing >> it? >> >> Solutions I can see are: >> >> 1. Allow concurrent logins >> 2. Allow concurrent logins but report that someone else is logged it - >> like Gmail does >> 3. Don't allow them and kick out any logged in user when a new one logs in >> 4. Don't allow them and lock out all new logins till old ones have logged >> out >> 5. Give a warning popup when logging in to say the account is in use >> elsewhere as well >> 6. Allow but report back to an admin or log tracker or similar >> >> 1 is the default in most cases. >> 2 is a good idea but really, how many people look at the little thing >> in Gmail which says where else the account is logged in from, I don't >> and I'm sure normal users don't even know it exists. >> 3. Good but if an attacker gets creds or a reliable session hijack >> then they can use them to DoS legit users by keep logging them out. >> 4. Good but if an attacker gets in they can keep the account active >> and so DoS the real user by never letting them log in. >> 5. Maybe the best option but only works in the legit user logs in >> second otherwise the attacker gets the warning and ignores it. >> 6. Good one if people are watching the logs and can act on them. >> >> What other options are there? Can it be done in a good way that makes >> if of any use? >> >> Robin >> >> >> >> This list is sponsored by Cenzic >> -------------------------------------- >> Let Us Hack You. Before Hackers Do! >> It's Finally Here - The Cenzic Website HealthCheck. FREE. >> Request Yours Now! >> http://www.cenzic.com/2009HClaunch_Securityfocus >> -------------------------------------- >> > This list is sponsored by Cenzic -------------------------------------- Let Us Hack You. Before Hackers Do! It's Finally Here - The Cenzic Website HealthCheck. FREE. Request Yours Now! http://www.cenzic.com/2009HClaunch_Securityfocus --------------------------------------