CVE-2021-21419

Improper Handling of Highly Compressed Data (Data Amplification) and Memory Allocation with Excessive Size Value in eventlet

Description

Eventlet is a concurrent networking library for Python. A websocket peer may exhaust memory on Eventlet side by sending very large websocket frames. Malicious peer may exhaust memory on Eventlet side by sending highly compressed data frame. A patch in version 0.31.0 restricts websocket frame to reasonable limits. As a workaround, restricting memory usage via OS limits would help against overall machine exhaustion, but there is no workaround to protect Eventlet process.

Category

5.3
CVSS
Severity: Medium
CVSS 3.1 •
CVSS 2.0 •
EPSS 0.17%
Vendor Advisory fedoraproject.org Vendor Advisory fedoraproject.org
Affected: eventlet eventlet
Published at:
Updated at:

References

Link Tags
https://github.com/eventlet/eventlet/security/advisories/GHSA-9p9m-jm8w-94p2 third party advisory
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/R5JZP4LZOSP7CUAM3GIRW6PIAWKH5VGB/ vendor advisory
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/2WJFSBPLCNSZNHYQC4QDRDFRTEZRMD2L/ vendor advisory

Frequently Asked Questions

What is the severity of CVE-2021-21419?
CVE-2021-21419 has been scored as a medium severity vulnerability.
How to fix CVE-2021-21419?
To fix CVE-2021-21419, 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-2021-21419 being actively exploited in the wild?
As for now, there are no information to confirm that CVE-2021-21419 is being actively exploited. According to its EPSS score, there is a ~0% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
What software or system is affected by CVE-2021-21419?
CVE-2021-21419 affects eventlet eventlet.
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