Topic "Putty 0.56 Security Fix"

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Sorry if this has already been posted, but I haven't seen it...

Another major Putty security hole has been patched... (yeah, 2 in 3 months Sad )

From the Putty website:
2004-10-26 ANOTHER SECURITY HOLE, fixed in PuTTY 0.56

PuTTY 0.56, released today, fixes a serious security hole which can allow a server to execute code of its choice on a PuTTY client connecting to it. In SSH2, the attack can be performed before host key verification, meaning that even if you trust the server you think you are connecting to, a different machine could be impersonating it and could launch the attack before you could tell the difference. We recommend everybody upgrade to 0.56 as soon as possible.

That's two really bad holes in three months. I'd like to apologise to all our users for the inconvenience.

Further details are available from iDEFENSE, here (<invalid hyperlink removed by admin>).


from iDEFENSE (<invalid hyperlink removed by admin>)
The vulnerability specifically exists due to insufficient bounds checking on SSH2_MSG_DEBUG packets. The 'stringlen' parameter is given a user-supplied value by reading in an integer from an offset in the packet data. The 'stringlen' value is incorrectly checked due to signedness issues as seen below.


So does 3.7 beta use PuTTy 0.56?

garylove wrote:
So does 3.7 beta use PuTTy 0.56?

WinSCP 3.7 Beta was released on 2004-10-12 and PuTTY's vulnerability was informed to PuTTY developmet team on 2004-10-21.
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WinSCP is the most probably vulnerable. I hope I can manage new release tomorrow.
Martin Prikryl

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