CVE-2021-28089

Description

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.

Category

7.5
CVSS
Severity: High
CVSS 3.1 •
CVSS 2.0 •
EPSS 1.69% Top 20%
Vendor Advisory fedoraproject.org Vendor Advisory gentoo.org Vendor Advisory torproject.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/40304 vendor advisory
https://blog.torproject.org/node/2009 release notes vendor advisory
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/HPDXB2GZHG3VNOTWSXQ3QZVHNV76WCU5/ vendor advisory
https://security.gentoo.org/glsa/202107-25 third party advisory vendor advisory

Frequently Asked Questions

What is the severity of CVE-2021-28089?
CVE-2021-28089 has been scored as a high severity vulnerability.
How to fix CVE-2021-28089?
To fix CVE-2021-28089, 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-2021-28089 being actively exploited in the wild?
It is possible that CVE-2021-28089 is being exploited or will be exploited in a near future based on public information. According to its EPSS score, there is a ~2% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
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