CVE catalog
CVE-2021-21419
python-eventlet: CVE-2021-21419
- Severity
- Medium · CVSS 5.3
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L - Published
- Source
- [NVD] · [CVE record]
- EPSS
- 1.79% · Oct 22, 2026
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.
Vulnerable and fixed packages
Distribution-reported package versions and fixes. These do not depend on matching against the OpenFactory package catalog.
| Distribution | Package | Release | Version | Status |
|---|---|---|---|---|
| Debian | python-eventlet | sid | 0.41.2-3 | fixed |
| Debian | python-eventlet | forky | 0.41.2-3 | fixed |
| Debian | python-eventlet | trixie | 0.39.1-2+deb13u1 | fixed |
| Debian | python-eventlet | bookworm | 0.33.1-4 | fixed |
| Ubuntu | python-eventlet | 20.04 | 0.25.0-0ubuntu1 | vulnerable |
| Ubuntu | python-eventlet | 20.04 | 0.25.1-2build1 | vulnerable |
| Ubuntu | python-eventlet | 20.04 | 0.25.1-2ubuntu1 | vulnerable |
| Ubuntu | python-eventlet | 20.04 | 0.25.1-2ubuntu1.1 | fixed |
| Ubuntu | python-eventlet | 20.04 | 0.25.0-0ubuntu1 | vulnerable |
| Ubuntu | python-eventlet | 20.04 | 0.25.1-2build1 | vulnerable |
| Ubuntu | python-eventlet | 20.04 | 0.25.1-2ubuntu1 | vulnerable |
| Ubuntu | python-eventlet | 20.04 | 0.25.1-2ubuntu1.1 | fixed |
Fixed-version evidence
| Distribution | Package | Type | Release | Fixed version | Urgency | Origin | Bugs |
|---|---|---|---|---|---|---|---|
| Debian | python-eventlet | source | sid | 0.26.1-7 | not yet assigned | Not reported | [988342] |
| Debian | python-eventlet | source | forky | 0.26.1-7 | not yet assigned | Not reported | [988342] |
| Debian | python-eventlet | source | trixie | 0.26.1-7 | not yet assigned | Not reported | [988342] |
| Debian | python-eventlet | source | bookworm | 0.26.1-7 | not yet assigned | Not reported | [988342] |
| Ubuntu | python-eventlet | deb | 20.04 | 0.25.1-2ubuntu1.1 | Not reported | USN-4956-1 | Not reported |
| Ubuntu | python-eventlet | deb | 20.04 | 0.25.1-2ubuntu1.1 | Not reported | UBUNTU-CVE-2021-21419 | Not reported |
OpenFactory catalog packages
[Debian 12 (Bookworm)]
- [python3-eventlet]Fixed
Source package: [python-eventlet]
Details (2)
0.33.1-4· all · bookwormFixed · Fixed:
0.26.1-7dsa · python-eventlet · debian · bookworm; dsa · python-eventlet · debian · 12
0.33.1-4· all · bookwormFixed · Fixed:
0.26.1-7dsa · python-eventlet · debian · bookworm; dsa · python-eventlet · debian · 12
- [python-eventlet-doc]Fixed
Source package: [python-eventlet]
Details (2)
0.33.1-4· all · bookwormFixed · Fixed:
0.26.1-7dsa · python-eventlet · debian · bookworm; dsa · python-eventlet · debian · 12
0.33.1-4· all · bookwormFixed · Fixed:
0.26.1-7dsa · python-eventlet · debian · bookworm; dsa · python-eventlet · debian · 12
[Debian 13 (Trixie)]
- [python3-eventlet]Fixed
Source package: [python-eventlet]
Details (2)
0.39.1-2+deb13u1· all · trixieFixed · Fixed:
0.26.1-7dsa · python-eventlet · debian · 13
0.39.1-2+deb13u1· all · trixieFixed · Fixed:
0.26.1-7dsa · python-eventlet · debian · 13
- [python-eventlet-doc]Fixed
Source package: [python-eventlet]
Details (2)
0.39.1-2+deb13u1· all · trixieFixed · Fixed:
0.26.1-7dsa · python-eventlet · debian · 13
0.39.1-2+deb13u1· all · trixieFixed · Fixed:
0.26.1-7dsa · python-eventlet · debian · 13
Observed:
References
- [https://access.redhat.com/errata/RHSA-2021:5071]
- [https://osv.dev/vulnerability/DEBIAN-CVE-2021-21419]
- [https://osv.dev/vulnerability/UBUNTU-CVE-2021-21419]
- [https://osv.dev/vulnerability/USN-4956-1]
- [https://security-tracker.debian.org/tracker/CVE-2021-21419]
- [https://wid.cert-bund.de/.well-known/csaf/white/2021/wid-sec-w-2024-0103.json]
[CERT-Bund public advisories] · [Debian Security Tracker] · [FIRST EPSS] · [OSV Package Vulnerability Database] · [Red Hat security advisories and VEX]