[Bro] Segmentation fault while using own signature.

[Vlad Grigorescu]

I could be mistaken, but some of these don't look like correct escape sequences for Bro regular expressions.

Check out the PATTERNS section of the flex documentation:

http://dinosaur.compilertools.net/flex/manpage.html

  --Vlad


fatema bannatwala <fatema.bannatwala at gmail.com> writes:

> Hi all,
>
> So I have a case where if I use following regex in sig file, it works, but
> when I edit it and make it more strict I get segmentation fault in like 5
> minutes after bro gets normally started:
>
> The working version:
>
> signature rootkit-potential {
>   payload /.*[0-9\.]{7,15}\|[0-9]{1,5}.*/
>   event "Potential rootkit"
>   tcp-state originator
> }
>
> signature rootkit-malware {
>   payload /.*SSH-2\.5-OpenSSH_6\.1\.9.[0-9\.]{7,15}\|\d{1,5}.*/
>   event "rootkit malware"
>   tcp-state originator
> }
>
> When I change regex to be more restrictive, Seg fault occurs:
>
> signature rootkit-potential {
>   payload /.*(?:\d{1,3}\.\d{1,3}\.\d{1,3}\.\d{1,3}\|\d{1,5}).*/
>   event "Potential rootkit"
>   tcp-state originator
> }
>
> signature rootkit-malware {
>   payload
> /.*SSH-2\.5-OpenSSH_6\.1\.9.(?:\d{1,3}\.\d{1,3}\.\d{1,3}\.\d{1,3}\|\d{1,5}).*/
>   event "rootkit malware"
>   tcp-state originator
> }
>
> Any idea what might be going wrong?
>
> Thanks,
> Fatema.
> _______________________________________________
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> bro at bro-ids.org
> http://mailman.ICSI.Berkeley.EDU/mailman/listinfo/bro
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