python-eventlet — security advisory
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.
- Products
- python-eventlet
- Affected versions
- Not specified
- Fixed versions
- 0.26.1-7
- CVEs
- CVE-2021-21419
- Confirmed fixed CVEs
- Not specified
- Updated in this feed
- 1 Nov 2026, 01:40 UTC · Revision 1
Source evidence
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.
osv:DEBIAN-CVE-2021-21419
python-eventlet
Fixed versions: 0.26.1-7
python-eventlet
Fixed versions: 0.26.1-7
python-eventlet
Fixed versions: 0.26.1-7
Complete source record
{
"id": "340225154da7cf4c404a117b71ff669f0a4ea42ab0b04ee0e564508db753c714",
"url": "https://osv.dev/vulnerability/DEBIAN-CVE-2021-21419",
"method": "structured",
"payload": {
"kind": "advisory",
"title": "DEBIAN-CVE-2021-21419",
"summary": "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.",
"evidence": "osv:DEBIAN-CVE-2021-21419",
"products": [
{
"name": {
"value": "python-eventlet",
"evidence": "/affected/0/package/name"
},
"prerequisites": [],
"fixed_versions": [
{
"value": "0.26.1-7",
"evidence": "/affected/0/ranges"
}
],
"affected_versions": []
},
{
"name": {
"value": "python-eventlet",
"evidence": "/affected/1/package/name"
},
"prerequisites": [],
"fixed_versions": [
{
"value": "0.26.1-7",
"evidence": "/affected/1/ranges"
}
],
"affected_versions": []
},
{
"name": {
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"evidence": "/affected/2/package/name"
},
"prerequisites": [],
"fixed_versions": [
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"evidence": "/affected/2/ranges"
}
],
"affected_versions": []
}
],
"severity": "medium",
"structured": {
"id": "DEBIAN-CVE-2021-21419",
"aliases": [
"DEBIAN-CVE-2021-21419"
],
"metrics": [
{
"type": "CVSS_V3",
"score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L"
}
],
"affected": [
{
"ranges": [
{
"type": "ECOSYSTEM",
"events": [
{
"introduced": "0"
},
{
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}
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],
"package": {
"name": "python-eventlet",
"purl": "pkg:deb/debian/python-eventlet?arch=source&distro=bookworm",
"ecosystem": "Debian:12"
},
"database_specific": {
"source": "https://storage.googleapis.com/debian-osv/debian-cve-osv/DEBIAN-CVE-2021-21419.json"
},
"ecosystem_specific": {
"urgency": "not yet assigned"
}
},
{
"ranges": [
{
"type": "ECOSYSTEM",
"events": [
{
"introduced": "0"
},
{
"fixed": "0.26.1-7"
}
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}
],
"package": {
"name": "python-eventlet",
"purl": "pkg:deb/debian/python-eventlet?arch=source&distro=trixie",
"ecosystem": "Debian:13"
},
"database_specific": {
"source": "https://storage.googleapis.com/debian-osv/debian-cve-osv/DEBIAN-CVE-2021-21419.json"
},
"ecosystem_specific": {
"urgency": "not yet assigned"
}
},
{
"ranges": [
{
"type": "ECOSYSTEM",
"events": [
{
"introduced": "0"
},
{
"fixed": "0.26.1-7"
}
]
}
],
"package": {
"name": "python-eventlet",
"purl": "pkg:deb/debian/python-eventlet?arch=source&distro=forky",
"ecosystem": "Debian:14"
},
"database_specific": {
"source": "https://storage.googleapis.com/debian-osv/debian-cve-osv/DEBIAN-CVE-2021-21419.json"
},
"ecosystem_specific": {
"urgency": "not yet assigned"
}
}
],
"modified": "2026-10-23T18:04:49.199549596Z",
"provider": "osv",
"upstream": [
"CVE-2021-21419"
],
"references": [
"https://security-tracker.debian.org/tracker/CVE-2021-21419"
]
},
"related_cves": [
{
"value": "CVE-2021-21419",
"evidence": "/upstream"
}
],
"security_relevant": true,
"severity_evidence": "/severity/0/score"
},
"source_id": "core-osv",
"document_id": 423967,
"published_at": "2021-05-07T15:15:07.407+00:00"
}