[asterisk-dev] Dialstring injection - security advisory release?

[Nick Lewis]

>A useful exploit of a buffer overflow 
>vulnerability takes much more 
>sophistication than an exploit based on 
>this issue, yet we (justifiably so) take 
>those issues _VERY_ seriously.  I don't 
>think this issue should be discounted.

I am glad that this issue is being taken seriously.

Perhaps it would be possible to see "&" protected in the same way that I
assume "," and "|" are, possibly by autoescaping them. It is agreed that
the main vunerability is in the Dial() application. It should be
straighforward to introduce new code in app_dial.c that disregards
escaped characters as syntax in place of the current parsing code:

while ((cur = strsep(&rest, "&")) ) {
...
}

(perhaps it could be done crudely after strsep with a check for the
presence '\' at cur-2 and if so the restoration of '&' at cur-1)

-- N_L

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