Resource exhaustion in Eventlet

CVE-2021-21419

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.

Vulnerability class: DoS (Denial of Service)

EPSS: 0.018 (76.3th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 5.3 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L.

Affected products

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2021-21419?
CVE-2021-21419 is a medium-severity vulnerability in Eventlet, classified under Uncontrolled Resource Consumption. CVSS score: 5.3/10. Published 2021-05-07.
How severe is CVE-2021-21419?
Medium severity. CVSS v3 base score is 5.3 out of 10.