CVE-2021-34549

Description

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.

Category

7.5
CVSS
Severity: High
CVSS 3.1 •
CVSS 2.0 •
EPSS 0.65%
Vendor Advisory gentoo.org Vendor Advisory torproject.org
Affected: n/a n/a
Published at:
Updated at:

References

Link Tags
https://gitlab.torproject.org/tpo/core/tor/-/issues/40391 broken link
https://blog.torproject.org/node/2041 release notes vendor advisory
https://security.gentoo.org/glsa/202107-25 third party advisory vendor advisory

Frequently Asked Questions

What is the severity of CVE-2021-34549?
CVE-2021-34549 has been scored as a high severity vulnerability.
How to fix CVE-2021-34549?
To fix CVE-2021-34549, make sure you are using an up-to-date version of the affected component(s) by checking the vendor release notes. As for now, there are no other specific guidelines available.
Is CVE-2021-34549 being actively exploited in the wild?
As for now, there are no information to confirm that CVE-2021-34549 is being actively exploited. According to its EPSS score, there is a ~1% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
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