CVE-2011-4895: Infoleak

Published Dec 23, 2011
·
Updated

Tor before 0.2.2.34, when configured as a bridge, sets up circuits through a process different from the process used by a client, which makes it easier for remote attackers to enumerate bridges by observing circuit building.

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-2011-4895?

CVE-2011-4895 has a medium severity rating as it allows remote attackers to potentially enumerate Tor bridges.

2

How do I fix CVE-2011-4895?

To fix CVE-2011-4895, upgrade to Tor version 0.2.2.34 or later.

3

What kind of attack does CVE-2011-4895 allow?

CVE-2011-4895 allows remote attackers to observe circuit building and gain information about Tor bridges.

4

Which versions of Tor are affected by CVE-2011-4895?

CVE-2011-4895 affects all Tor versions prior to 0.2.2.34.

5

Is CVE-2011-4895 a client or server vulnerability?

CVE-2011-4895 is considered a server-side vulnerability related to the configuration of Tor as a bridge.

Company

Resources

Contact

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