Re: Security Question

From: Pete Finnigan <>
Date: Fri, 06 Feb 2009 16:04:30 +0000
Message-ID: <>

Hi Connor,

Thanks for your input; I agree totally. the ALTER SESSION system privilege is dangerous as it can move data outside of the database and potentially allow reading of data from an account that has no privileges on the data.

Whilst I made a mess of editing my post yesterday my point was valid. This lead me to think about what is possible with just ALTER SESSION and i have spent a little time playing this lunch time and I have been able to read credit cards, get password hashes, dump data blocks, work out structure and more. I wrote a second blog entry describing how this can be done - -


So yes to answer your question it is possible ti dump data blocks with ALTER SESSION but not from the files themselves. This is not an issue for someone who wants to steal data; they do not consider the source; they consider the result!



Connor McDonald wrote:

> On Fri, Feb 6, 2009 at 6:22 PM, Pete Finnigan <> wrote:

>> Hi Christopher,
>> Thanks for your email. Yes you are right of course. I actually didnt
>> mean to suggest that block dumps were possible with alter session but
>> added the word block because of brain fade.
>> Alex also picked up the same issue.
>> I have edited the post and replied to Alex's comment. The post is
>> Thanks for keeping me honest
>> kind regards
>> Pete
> Either way...when you see what's possible in oraus.msg with "alter session
> set events" its not the kind of privilege you want to be handing out on a
> whim...  If possible, wrap the desired command up in a controlled proc and
> give access to that.


Pete Finnigan
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Received on Fri Feb 06 2009 - 10:04:30 CST

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