CVE-2021-21419: Improper Handling of Highly Compressed Data (Data Amplification) and Memory Allocation with Excessive Size Value in eventlet

CVE-2021-21419 · Severity: low · CVSS 3.1 · Published 2021-05-07

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.

Technologies: eventlet (PyPI). Vendors: PyPI.

Quick answers

Is CVE-2021-21419 exploited in the wild?
No. Junglewise Threat Intelligence has no report of CVE-2021-21419 being exploited in the wild.
How severe is CVE-2021-21419?
Low severity, with a CVSS score of 3.1, published 7 May 2021.
Which products and versions are affected?
eventlet (PyPI) ECOSYSTEM:introduced=0.10,fixed=0.31.0, ECOSYSTEM:introduced=0.10.0,fixed=0.31.0.
Is there a fix for CVE-2021-21419?
Yes. eventlet (PyPI): upgrade to 0.31.0 or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.
Am I affected by CVE-2021-21419?
Check whether you run eventlet (PyPI) at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

How to fix

  • eventlet (PyPI): upgrade to 0.31.0 or later
    pip install "eventlet>=0.31.0"

Affected products

  • eventlet (PyPI) ECOSYSTEM:introduced=0.10,fixed=0.31.0, ECOSYSTEM:introduced=0.10.0,fixed=0.31.0

Identifiers

  • CVE-2021-21419
  • GHSA-9p9m-jm8w-94p2
  • PYSEC-2021-12

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