CVE-2021-28089: High severity tor project tor vulnerability

Published Mar 19, 2021
·
Updated

Tor before 0.4.5.7 allows a remote participant in the Tor directory protocol to exhaust CPU resources on a target, aka TROVE-2021-001.

Affected Software

8 affected components
torproject Tor<0.3.5.14
torproject Tor>=0.4.4.4<0.4.4.8
torproject Tor>=0.4.5.0<0.4.5.7
torproject Tor=0.4.4.0-alpha
torproject Tor=0.4.4.1-alpha
torproject Tor=0.4.4.2-alpha
torproject Tor=0.4.4.3-alpha
Fedoraproject Fedora=33

Event History

Mar 19, 2021
CVE Published
via MITRE·04:18 AM
Data Sourced
via MITRE·04:18 AM
Description
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Frequently Asked Questions

1

What is CVE-2021-28089?

CVE-2021-28089 is a vulnerability in Tor before version 0.4.5.7 that allows a remote participant in the Tor directory protocol to exhaust CPU resources on a target.

2

What is the severity of CVE-2021-28089?

The severity of CVE-2021-28089 is high with a CVSS score of 7.5.

3

What software versions are affected by CVE-2021-28089?

Versions of Tor up to and including 0.3.5.14, 0.4.4.4 to 0.4.4.8, and 0.4.5.0 to 0.4.5.7 are affected by CVE-2021-28089.

4

How can a remote participant exhaust CPU resources on a target using CVE-2021-28089?

A remote participant in the Tor directory protocol can exhaust CPU resources on a target by exploiting the vulnerability in Tor before version 0.4.5.7.

5

How can I fix CVE-2021-28089?

To fix CVE-2021-28089, update Tor to version 0.4.5.7 or later.

Contact

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