CVE-2009-0654: Medium severity Tor (The Onion Router) vulnerability

Published Feb 20, 2009
·
Updated

Tor 0.2.0.28, and probably 0.2.0.34 and earlier, allows remote attackers, with control of an entry router and an exit router, to confirm that a sender and receiver are communicating via vectors involving (1) replaying, (2) modifying, (3) inserting, or (4) deleting a single cell, and then observing cell recognition errors at the exit router. NOTE: the vendor disputes the significance of this issue, noting that the product's design "accepted end-to-end correlation as an attack that is too expensive to solve."

Affected Software

33 affected components
Tor (The Onion Router)<=0.2.0.34
Tor (The Onion Router)=0.2.0.1-alpha
Tor (The Onion Router)=0.2.0.2-alpha
Tor (The Onion Router)=0.2.0.3-alpha
Tor (The Onion Router)=0.2.0.4-alpha
Tor (The Onion Router)=0.2.0.5-alpha
Tor (The Onion Router)=0.2.0.6-alpha
Tor (The Onion Router)=0.2.0.7-alpha
Tor (The Onion Router)=0.2.0.8-alpha
Tor (The Onion Router)=0.2.0.9-alpha
Tor (The Onion Router)=0.2.0.10-alpha
Tor (The Onion Router)=0.2.0.11-alpha
Tor (The Onion Router)=0.2.0.12-alpha
Tor (The Onion Router)=0.2.0.13-alpha
Tor (The Onion Router)=0.2.0.14-alpha
Tor (The Onion Router)=0.2.0.15-alpha
Tor (The Onion Router)=0.2.0.16-alpha
Tor (The Onion Router)=0.2.0.17-alpha
Tor (The Onion Router)=0.2.0.18-alpha
Tor (The Onion Router)=0.2.0.19-alpha
Tor (The Onion Router)=0.2.0.20-alpha
Tor (The Onion Router)=0.2.0.21-alpha
Tor (The Onion Router)=0.2.0.22-alpha
Tor (The Onion Router)=0.2.0.23-alpha
Tor (The Onion Router)=0.2.0.24-alpha
Tor (The Onion Router)=0.2.0.25-alpha
Tor (The Onion Router)=0.2.0.26-alpha
Tor (The Onion Router)=0.2.0.27-alpha
Tor (The Onion Router)=0.2.0.28-alpha
Tor (The Onion Router)=0.2.0.29-alpha
Tor (The Onion Router)=0.2.0.30-alpha
Tor (The Onion Router)=0.2.0.31-alpha
Tor (The Onion Router)=0.2.0.32-alpha

Event History

Feb 20, 2009
CVE Published
via MITRE·07:00 PM
Data Sourced
via MITRE·07:00 PM
Description
Data Sourced
via NVD·07:30 PM
DescriptionSeverityAffected Software

Frequently Asked Questions

1

What is the severity of CVE-2009-0654?

CVE-2009-0654 is classified as a medium severity vulnerability that impacts the anonymity of users on the Tor network.

2

How do I fix CVE-2009-0654?

To mitigate CVE-2009-0654, it is recommended to upgrade to a later version of Tor that addresses this vulnerability.

3

What versions of Tor are affected by CVE-2009-0654?

CVE-2009-0654 affects Tor versions from 0.2.0.28 down to 0.2.0.1-alpha.

4

What type of attacks does CVE-2009-0654 enable?

CVE-2009-0654 allows attackers with control of both an entry and exit router to potentially correlate communications.

5

Is it safe to use Tor versions affected by CVE-2009-0654?

Using affected Tor versions can compromise privacy and anonymity, so it is not recommended.

Contact

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