Security issues
Supybot git repository was declared dead on 2018-05-10 and archived on GitHub. v0.84.0 was the last release at that time. 0.83.4.1 used to be a very common release available through several Linux distributions for years and thus I made this page, which I guess is now available more of for historical reasons.
WARNING: most of the content originates from 2014!
The issues of 0.83.4.1.
1. Anyone can crash it and computer where it’s running on
And this is very easy. Just run the command
!misc last --regexp m/(.*\w){512}/
where ! is the prefix character.
Misc is loaded by default and cannot be unloaded without modifying the config.
2. The previous wasn’t the only way to do this
Everyone can also make the bot count an equation, which brings it and the host computer down.
For example:
!math calc factorial(999999)
This requires Math plugin which comes with Supybot, but isn’t load by default.
- Limnoria issue #354
- Fixing commit: 695078e
- Ubuntu bug #996950
- Debian bug 672215
3. Anyone can access network services via the bot.
I don’t have example command for this, but it happens by nesting “format cut” and “misc tell”.
What does this mean? Anyone can tell the bot to ghost someone else on same account, take over a channel by telling the bot to give flags (if it has correct flags), change password of the account and everything else what you do with network services.
- This was only reported at IRC and I am unable to find issue report or fixing commit. ~~Mikaela on 2015-01-04.
4. Web page with special characters in <title> can be used to send DCC/CTCP commands.
This doesn’t mean only things like CTCP actions (also known as /me), but known
problems with old routers ( FF ? DCC SEND “ff???f??????????????” 0 0 0
) which
make them reconnect to the internet.
Usage:
!web title <malicious.page.here>
!web fetch <malicious.page.here>
This was only reported at IRC and I am unable to find issue report or fixing commit. ~~Mikaela on 2015-01-04.
5. Web Titlte/Fetch can be used for DoS
They are vulnerable to queries to servers which have custom headers which can lead to DoS.
This was only reported at IRC and I am unable to find issue report or fixing commit. ~~Mikaela on 2015-01-04.
6. QuoteGrabs grab command also works in PM
and can grab private content such as user register
or user identify
or with
the case of owner possibly NickServ passwords and others not so nice things.
- It appears this issue was only reported at IRC.
- Fixing commit: a3346343679f3bdf8c77d9efb5a2097e215d51df
Are these issues publicly known?
Of course they are. Issue reports are below the actual issues.
The first issue has been also used to take down some of Ubuntu IRC bots several times. At least UbotX (I don’t remember the number) and meetingology.
Some of these issues are fixed in git repository, but most people aren’t using it. If you wish to start using it, please scroll down to installation instructions lower this page even though Limnoria and gribble are more recommended.
How to avoid them?
You can add anticapability for these commands using owner defaultcapability
,
but that is only a temporary solution. There can also be other issues.
There are also two active Supybot forks, known as Limnoria and Gribble, which are actively developed and have fixed these issues. If you want permanent solution, you should install either of them.
Possibly interesting links
- Comparsion of commit activity between Limnoria, Gribble and Supybot.
- Gribble’s modifications to stock Supybot
- Limnoria’s modifications to Gribble.
- Features of Gribble are fully merged to Limnoria.
Your current botname.conf is 100% compatible with forks.
Join Supybot channels on LiberaChat!
Installing forks
This section has been removed in order to not duplicate Limnoria’s documentation.
Do you know issue that isn’t mentioned here? If it’s not already reported, please report it on Limnoria’s issue tracker. If it’s known, but just not reported here, please feel free to add it.