Home/CVE/Eventlet is a concurrent networking library for Python. A websocket peer may exhaust memory on Eventlet side by sending
CVE

CVE-2021-21419

Eventlet is a concurrent networking library for Python. A websocket peer may exhaust memory on Eventlet side by sending

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.

MEDIUM · CVSS 5.3 EPSS 0.0013
Monitor
  • No active-exploitation, high-EPSS, or public-exploit signals - routine patching cadence
Sigma rules0 YARA rules0
⬡

Weakness Classification

CWE-400Uncontrolled Resource Consumption
▤

Affected Products & Versions

2
eventlet>= 0.10 and < 0.31.0
fedoraproject fedoraall versions
▤

Affected Packages

1
Language-ecosystem packages (from OSV) tied to this CVE, with the version that fixes it - the dependency-level detail NVD doesn’t carry.
PyPI eventlet MODERATE fixed in 0.31.0
▣

Scoring & Timeline

5.3
MEDIUM · CVSS v3.1 · security-advisories@github.com
View on NVD
Attack Vector
Network Adjacent Local Physical
Attack Complexity
Low High
Privileges Required
None Low High
User Interaction
None Required
Scope
Unchanged Changed
Confidentiality
None Low High
Integrity
None Low High
Availability
None Low High
Published to NVD07 May 2021 · 03:15 PM
CVSS VectorCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L
⚑

Vendor Advisories

8
rhsaRHSA-2023:6128Moderate
rhsaRHSA-2024:0213Moderate
rhsaRHSA-2024:0188Moderate
suse-csafSUSE-SU-2021:3729-1
suse-csafSUSE-SU-2021:2554-1
🔗

References & Sources

3
Source URLs (vendor pages, mailing lists, write-ups). Exploit/PoC links are in their own section above to avoid duplication.
https://github.com/eventlet/eventlet/security/advisories/GHSA-9p9m-jm8w-94p2Third Party Advisory
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/2WJFSBPLCNSZNHYQC4QDRDFRTEZRMD2L/
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/R5JZP4LZOSP7CUAM3GIRW6PIAWKH5VGB/
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