CVE-2021-34549
First published: Tue Jun 29 2021(Updated: )
An issue was discovered in Tor before 0.4.6.5, aka TROVE-2021-005. Hashing is mishandled for certain retrieval of circuit data. Consequently. an attacker can trigger the use of an attacker-chosen circuit ID to cause algorithm inefficiency.
Credit: cve@mitre.org
| Affected Software | Affected Version | How to fix |
|---|---|---|
| Torproject Tor | <0.3.5.15 | |
| Torproject Tor | >=0.4.0.0<0.4.4.9 | |
| Torproject Tor | >=0.4.5.0<0.4.5.9 | |
| Torproject Tor | >=0.4.6.0<0.4.6.5 |
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Reference Links
Frequently Asked Questions
What is CVE-2021-34549?
CVE-2021-34549 is a vulnerability discovered in Tor before 0.4.6.5, which mishandles hashing for certain retrieval of circuit data, allowing an attacker to cause algorithm inefficiency.
What is the severity of CVE-2021-34549?
CVE-2021-34549 has a severity rating of 7.5 (High).
How does CVE-2021-34549 affect Torproject Tor?
CVE-2021-34549 affects Torproject Tor versions up to and including 0.4.6.5.
How can an attacker exploit CVE-2021-34549?
An attacker can exploit CVE-2021-34549 by triggering the use of an attacker-chosen circuit ID, leading to algorithm inefficiency.
How can I fix CVE-2021-34549?
To fix CVE-2021-34549, update Torproject Tor to version 0.4.6.6 or later.
- collector/nvd-index
- agent/event
- agent/references
- agent/weakness
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- agent/description
- agent/last-modified-date
- agent/softwarecombine
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- agent/tags
- collector/mitre-cve
- source/MITRE
- vendor/torproject
- canonical/torproject tor
- version/torproject tor/0.4.0.0
- version/torproject tor/0.4.5.0
- version/torproject tor/0.4.6.0