CVE-2011-2768: Medium severity tor (the onion router) vulnerability

Published Dec 23, 2011
·
Updated

Tor before 0.2.2.34, when configured as a client or bridge, sends a TLS certificate chain as part of an outgoing OR connection, which allows remote relays to bypass intended anonymity properties by reading this chain and then determining the set of entry guards that the client or bridge had selected.

Affected Software

229 affected components
Tor (The Onion Router)=0.2.1.1.14
Tor (The Onion Router)=0.2.1.10-alpha
Tor (The Onion Router)=0.2.2.17-alpha
Tor (The Onion Router)=0.1.1.6
Tor (The Onion Router)=0.2.1.26
Tor (The Onion Router)=0.1.1.2-alpha
Tor (The Onion Router)=0.2.1.1.4-alpha
Tor (The Onion Router)=0.2.1.1.1-alpha
Tor (The Onion Router)=0.1.1.9
Tor (The Onion Router)=0.0.6.2
Tor (The Onion Router)=0.2.1.1.12
Tor (The Onion Router)=0.2.1.1.8-alpha
Tor (The Onion Router)=0.1.0.18
Tor (The Onion Router)=0.2.2.8-alpha
Tor (The Onion Router)=0.1.1.9-alpha
Tor (The Onion Router)=0.2.1.1.16
Tor (The Onion Router)=0.2.0.30
Tor (The Onion Router)=0.2.2.5-alpha
Tor (The Onion Router)=0.1.1.23
Tor (The Onion Router)=0.2.1.1.27
Tor (The Onion Router)=0.0.5
Tor (The Onion Router)=0.2.0.11-alpha
Tor (The Onion Router)=0.1.0.7
Tor (The Onion Router)=0.1.1.6-alpha
Tor (The Onion Router)=0.0.9.8
Tor (The Onion Router)=0.0.9.10
Tor (The Onion Router)=0.1.1.19
Tor (The Onion Router)=0.1.2.18
Tor (The Onion Router)=0.0.9.2
Tor (The Onion Router)=0.1.2.10
Tor (The Onion Router)=0.2.0.22-alpha
Tor (The Onion Router)=0.2.2.11-alpha
Tor (The Onion Router)=0.2.1.8-alpha
Tor (The Onion Router)=0.0.7
Tor (The Onion Router)=0.2.2.5
Tor (The Onion Router)=0.2.0.19-alpha
Tor (The Onion Router)=0.1.0.10
Tor (The Onion Router)=0.2.1.25
Tor (The Onion Router)=0.1.2.9
Tor (The Onion Router)=0.2.0.31-alpha
Tor (The Onion Router)=0.2.0.14-alpha
Tor (The Onion Router)=0.0.9
Tor (The Onion Router)=0.1.0.8
Tor (The Onion Router)=0.2.1.1.2-alpha
Tor (The Onion Router)=0.2.1.28
Tor (The Onion Router)=0.2.1.1.18
Tor (The Onion Router)=0.2.1.13
Tor (The Onion Router)=0.2.0.28-alpha
Tor (The Onion Router)=0.2.1.1.17
Tor (The Onion Router)=0.0.9.5
Tor (The Onion Router)=0.1.0.12
Tor (The Onion Router)=0.0.9.3
Tor (The Onion Router)=0.1.2.5
Tor (The Onion Router)=0.2.1.5-alpha
Tor (The Onion Router)=0.2.0.35
Tor (The Onion Router)=0.1.2.16
Tor (The Onion Router)=0.2.1.17
Tor (The Onion Router)=0.1.1.26
Tor (The Onion Router)=0.2.0.17-alpha
Tor (The Onion Router)=0.0.8
Tor (The Onion Router)=0.2.2.1-alpha
Tor (The Onion Router)=0.0.9.9
Tor (The Onion Router)=0.2.0.25-alpha
Tor (The Onion Router)=0.1.1.17
Tor (The Onion Router)=0.2.2.29
Tor (The Onion Router)=0.1.0.5
Tor (The Onion Router)=0.1.2.14
Tor (The Onion Router)=0.1.0.2
Tor (The Onion Router)=0.2.1.19
Tor (The Onion Router)=0.1.0.1
Tor (The Onion Router)=0.1.1.1-alpha
Tor (The Onion Router)=0.2.1.1.24
Tor (The Onion Router)=0.2.2.2
Tor (The Onion Router)=0.2.1.1.25
Tor (The Onion Router)=0.2.0.26-alpha
Tor (The Onion Router)=0.2.0.12-alpha
Tor (The Onion Router)=0.1.1.2
Tor (The Onion Router)=0.2.1.7-alpha
Tor (The Onion Router)=0.2.0.3-alpha
Tor (The Onion Router)=0.1.2.6-alpha
Tor (The Onion Router)=0.2.0.7-alpha
Tor (The Onion Router)=0.2.1.9-alpha
Tor (The Onion Router)=0.1.2.15
Tor (The Onion Router)=0.2.0.29
Tor (The Onion Router)=0.2.1.27
Tor (The Onion Router)=0.1.1.8
Tor (The Onion Router)=0.1.2.1-alpha-cvs
Tor (The Onion Router)=0.2.0.18-alpha
Tor (The Onion Router)=0.1.1.5
Tor (The Onion Router)=0.2.2.29-beta
Tor (The Onion Router)=0.1.1.7-alpha
Tor (The Onion Router)=0.2.0.4-alpha
Tor (The Onion Router)=0.1.0.13
Tor (The Onion Router)=0.1.0.19
Tor (The Onion Router)=0.1.1.3-alpha
Tor (The Onion Router)=0.2.2.6-alpha
Tor (The Onion Router)=0.2.2.3
Tor (The Onion Router)=0.2.0.27-alpha
Tor (The Onion Router)=0.2.2.14-alpha
Tor (The Onion Router)=0.2.2.12-alpha
Tor (The Onion Router)=0.2.1.14
Tor (The Onion Router)=0.2.1.23
Tor (The Onion Router)=0.1.0.3
Tor (The Onion Router)=0.0.7.1
Tor (The Onion Router)=0.2.1.3-alpha
Tor (The Onion Router)=0.0.6
Tor (The Onion Router)=0.1.0.14
Tor (The Onion Router)=0.2.0.32-alpha
Tor (The Onion Router)=0.1.1.12
Tor (The Onion Router)=0.1.1.16
Tor (The Onion Router)<=0.2.2.33
Tor (The Onion Router)=0.2.0.15-alpha
Tor (The Onion Router)=0.2.1.12
Tor (The Onion Router)=0.2.0.9-alpha
Tor (The Onion Router)=0.1.2.1-alpha
Tor (The Onion Router)=0.1.1.10-alpha
Tor (The Onion Router)=0.0.3
Tor (The Onion Router)=0.2.1.6-alpha
Tor (The Onion Router)=0.1.1.18
Tor (The Onion Router)=0.0.9.4
Tor (The Onion Router)=0.1.1.15
Tor (The Onion Router)=0.2.0.2-alpha
Tor (The Onion Router)=0.2.1.4-alpha
Tor (The Onion Router)=0.1.1.21
Tor (The Onion Router)=0.1.1.4-alpha
Tor (The Onion Router)=0.2.1.29
Tor (The Onion Router)=0.1.2.4
Tor (The Onion Router)=0.1.2.11
Tor (The Onion Router)=0.2.0.8-alpha
Tor (The Onion Router)=0.2.2.19-alpha
Tor (The Onion Router)=0.1.0.15
Tor (The Onion Router)=0.1.2.19
Tor (The Onion Router)=0.1.2.7-alpha
Tor (The Onion Router)=0.0.6.1
Tor (The Onion Router)=0.2.1.1.19
Tor (The Onion Router)=0.2.1.1.13
Tor (The Onion Router)=0.2.1.22
Tor (The Onion Router)=0.0.2
Tor (The Onion Router)=0.2.2.3-alpha
Tor (The Onion Router)=0.1.1.14
Tor (The Onion Router)=0.2.1.1.7-alpha
Tor (The Onion Router)=0.2.0.24-alpha
Tor (The Onion Router)=0.2.2.2-alpha
Tor (The Onion Router)=0.2.2.6
Tor (The Onion Router)=0.1.2.3-alpha
Tor (The Onion Router)=0.2.1.18
Tor (The Onion Router)=0.1.0.6
Tor (The Onion Router)=0.2.1.1.22
Tor (The Onion Router)=0.2.0.33
Tor (The Onion Router)=0.2.0.34-alpha
Tor (The Onion Router)=0.1.1.3
Tor (The Onion Router)=0.2.1.1.21
Tor (The Onion Router)=0.2.2.1
Tor (The Onion Router)=0.2.2.10-alpha
Tor (The Onion Router)=0.2.0.21-alpha
Tor (The Onion Router)=0.1.2.31
Tor (The Onion Router)=0.2.1.1.5-alpha
Tor (The Onion Router)=0.1.0.9
Tor (The Onion Router)=0.1.1
Tor (The Onion Router)=0.2.1.1.28
Tor (The Onion Router)=0.1.1.22
Tor (The Onion Router)=0.2.1.1.10-alpha
Tor (The Onion Router)=0.1.2.2
Tor (The Onion Router)=0.2.2.32
Tor (The Onion Router)=0.0.7.3
Tor (The Onion Router)=0.1.2.8-beta
Tor (The Onion Router)=0.0.7.2
Tor (The Onion Router)=0.2.2.20-alpha
Tor (The Onion Router)=0.2.1.20
Tor (The Onion Router)=0.1.2.13
Tor (The Onion Router)=0.1.1.1
Tor (The Onion Router)=0.1.0.16
Tor (The Onion Router)=0.2.0.20-alpha
Tor (The Onion Router)=0.2.2.16-alpha
Tor (The Onion Router)=0.2.1.16
Tor (The Onion Router)=0.2.1.1-alpha
Tor (The Onion Router)=0.2.1.12-alpha
Tor (The Onion Router)=0.2.1.1.12-alpha
Tor (The Onion Router)=0.0.9.1
Tor (The Onion Router)=0.2.1.15
Tor (The Onion Router)=0.2.1.21
Tor (The Onion Router)=0.1.1.10
Tor (The Onion Router)=0.2.2.4-alpha
Tor (The Onion Router)=0.2.2.13-alpha
Tor (The Onion Router)=0.2.0.13-alpha
Tor (The Onion Router)=0.2.1.11-alpha
Tor (The Onion Router)=0.2.2.4
Tor (The Onion Router)=0.2.2.7-alpha
Tor (The Onion Router)=0.2.0.31
Tor (The Onion Router)=0.0.9.7
Tor (The Onion Router)=0.2.0.1-alpha
Tor (The Onion Router)=0.1.1.20
Tor (The Onion Router)=0.2.0.23-alpha
Tor (The Onion Router)=0.1.0.17
Tor (The Onion Router)=0.2.1.1.3-alpha
Tor (The Onion Router)=0.1.1.7
Tor (The Onion Router)=0.2.1.1.11-alpha
Tor (The Onion Router)=0.2.0.10-alpha
Tor (The Onion Router)=0.0.8.1
Tor (The Onion Router)=0.0.4
Tor (The Onion Router)=0.2.1.2-alpha
Tor (The Onion Router)=0.2.1.1.26
Tor (The Onion Router)=0.2.1.1.23
Tor (The Onion Router)=0.2.1.1.20
Tor (The Onion Router)=0.2.2.18-alpha
Tor (The Onion Router)=0.1.1.5-alpha
Tor (The Onion Router)=0.1.1.25
Tor (The Onion Router)=0.1.0.4
Tor (The Onion Router)=0.2.1.24
Tor (The Onion Router)=0.0.9.6
Tor (The Onion Router)=0.2.2.9-alpha
Tor (The Onion Router)=0.1.1.13
Tor (The Onion Router)=0.2.1.1.15
Tor (The Onion Router)=0.2.2.15-alpha
Tor (The Onion Router)=0.1.2.30
Tor (The Onion Router)=0.2.1.1.6-alpha
Tor (The Onion Router)=0.1.0.11
Tor (The Onion Router)=0.1.1.11
Tor (The Onion Router)=0.1.2.17
Tor (The Onion Router)=0.2.0.29-alpha
Tor (The Onion Router)=0.1.2.12
Tor (The Onion Router)=0.1.2.5-alpha
Tor (The Onion Router)=0.2.0.30-alpha
Tor (The Onion Router)=0.2.1.1.9-alpha
Tor (The Onion Router)=0.2.0.6-alpha
Tor (The Onion Router)=0.1.1.8-alpha
Tor (The Onion Router)=0.2.0.16-alpha
Tor (The Onion Router)=0.1.1.4
Tor (The Onion Router)=0.2.0.5-alpha

Remediation

Patch Available

https://blog.torproject.org/blog/tor-02234-released-security-patches

Event History

Dec 23, 2011
CVE Published
via MITRE·02:00 AM
Data Sourced
via MITRE·02:00 AM
Description

Frequently Asked Questions

1

What is the severity of CVE-2011-2768?

The severity of CVE-2011-2768 is rated as moderate.

2

How do I fix CVE-2011-2768?

To fix CVE-2011-2768, upgrade to Tor version 0.2.2.34 or later.

3

What software is affected by CVE-2011-2768?

CVE-2011-2768 affects several versions of Tor including 0.2.1.1.14, 0.2.1.10-alpha, and others up to 0.2.2.33.

4

What impact does CVE-2011-2768 have on anonymity?

CVE-2011-2768 can potentially allow remote relays to deduce a client's entry guards, compromising anonymity.

5

Is CVE-2011-2768 still relevant today?

While CVE-2011-2768 is an older vulnerability, it remains relevant for users of affected legacy versions of Tor.

Company

Resources

Contact

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