[SA18576] Tor Hidden Service Disclosure Weakness

TITLE:
Tor Hidden Service Disclosure Weakness

SECUNIA ADVISORY ID:
SA18576

VERIFY ADVISORY:
http://secunia.com/advisories/18576/

CRITICAL:
Less critical

IMPACT:
Exposure of sensitive information

WHERE:
>From remote

SOFTWARE:
Tor 0.x
http://secunia.com/product/5269/

DESCRIPTION:
Lasse Overlier and Paul Syverson have reported a weakness in Tor,
which can be exploited by malicious people to disclose certain
sensitive information.

The weakness is caused due to a design error in Tor. This can be
exploited to reveal the location of a hidden service more quickly
than was previously thought by setting up a malicious Tor server and
accessing the hidden service repeatedly while keeping track of who
builds circuits through the malicious server shortly after each
access.

The weakness has been reported in all stable versions and all
experimental versions through 0.1.1.10-alpha.

SOLUTION:
The weakness has been fixed in version 0.1.1.12-alpha.

PROVIDED AND/OR DISCOVERED BY:
Lasse Overlier and Paul Syverson

ORIGINAL ADVISORY:
http://archives.seul.org/or/announce/Jan-2006/msg00001.html

About:
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vulnerabilities.

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