HighFix available
netty — security advisory
The ZlibDecoders in Netty 4.1.x before 4.1.46 allow for unbounded memory allocation while decoding a ZlibEncoded byte stream. An attacker could send a large ZlibEncoded byte stream to the Netty server, forcing the server to allocate all of its free memory to a single decoder.
- Products
- netty
- Affected versions
- Not specified
- Fixed versions
- 1:4.1.48-1
- CVEs
- CVE-2020-11612
- Confirmed fixed CVEs
- Not specified
- Updated in this feed
- 1 Nov 2026, 12:56 UTC · Revision 1
Source evidence
The ZlibDecoders in Netty 4.1.x before 4.1.46 allow for unbounded memory allocation while decoding a ZlibEncoded byte stream. An attacker could send a large ZlibEncoded byte stream to the Netty server, forcing the server to allocate all of its free memory to a single decoder.
osv:DEBIAN-CVE-2020-11612
netty
Fixed versions: 1:4.1.48-1
netty
Fixed versions: 1:4.1.48-1
netty
Fixed versions: 1:4.1.48-1
Complete source record
{
"id": "7197b497cf4bca0d2cf5d626daec9c8a4148436c6c27d105d6b715efd7f922ac",
"url": "https://osv.dev/vulnerability/DEBIAN-CVE-2020-11612",
"method": "structured",
"payload": {
"kind": "advisory",
"title": "DEBIAN-CVE-2020-11612",
"summary": "The ZlibDecoders in Netty 4.1.x before 4.1.46 allow for unbounded memory allocation while decoding a ZlibEncoded byte stream. An attacker could send a large ZlibEncoded byte stream to the Netty server, forcing the server to allocate all of its free memory to a single decoder.",
"evidence": "osv:DEBIAN-CVE-2020-11612",
"products": [
{
"name": {
"value": "netty",
"evidence": "/affected/0/package/name"
},
"prerequisites": [],
"fixed_versions": [
{
"value": "1:4.1.48-1",
"evidence": "/affected/0/ranges"
}
],
"affected_versions": []
},
{
"name": {
"value": "netty",
"evidence": "/affected/1/package/name"
},
"prerequisites": [],
"fixed_versions": [
{
"value": "1:4.1.48-1",
"evidence": "/affected/1/ranges"
}
],
"affected_versions": []
},
{
"name": {
"value": "netty",
"evidence": "/affected/2/package/name"
},
"prerequisites": [],
"fixed_versions": [
{
"value": "1:4.1.48-1",
"evidence": "/affected/2/ranges"
}
],
"affected_versions": []
}
],
"severity": "high",
"structured": {
"id": "DEBIAN-CVE-2020-11612",
"aliases": [
"DEBIAN-CVE-2020-11612"
],
"metrics": [
{
"type": "CVSS_V3",
"score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H"
}
],
"affected": [
{
"ranges": [
{
"type": "ECOSYSTEM",
"events": [
{
"introduced": "0"
},
{
"fixed": "1:4.1.48-1"
}
]
}
],
"package": {
"name": "netty",
"purl": "pkg:deb/debian/netty?arch=source&distro=bookworm",
"ecosystem": "Debian:12"
},
"database_specific": {
"source": "https://storage.googleapis.com/debian-osv/debian-cve-osv/DEBIAN-CVE-2020-11612.json"
},
"ecosystem_specific": {
"urgency": "not yet assigned"
}
},
{
"ranges": [
{
"type": "ECOSYSTEM",
"events": [
{
"introduced": "0"
},
{
"fixed": "1:4.1.48-1"
}
]
}
],
"package": {
"name": "netty",
"purl": "pkg:deb/debian/netty?arch=source&distro=trixie",
"ecosystem": "Debian:13"
},
"database_specific": {
"source": "https://storage.googleapis.com/debian-osv/debian-cve-osv/DEBIAN-CVE-2020-11612.json"
},
"ecosystem_specific": {
"urgency": "not yet assigned"
}
},
{
"ranges": [
{
"type": "ECOSYSTEM",
"events": [
{
"introduced": "0"
},
{
"fixed": "1:4.1.48-1"
}
]
}
],
"package": {
"name": "netty",
"purl": "pkg:deb/debian/netty?arch=source&distro=forky",
"ecosystem": "Debian:14"
},
"database_specific": {
"source": "https://storage.googleapis.com/debian-osv/debian-cve-osv/DEBIAN-CVE-2020-11612.json"
},
"ecosystem_specific": {
"urgency": "not yet assigned"
}
}
],
"modified": "2026-10-26T12:01:20.549267082Z",
"provider": "osv",
"upstream": [
"CVE-2020-11612"
],
"references": [
"https://security-tracker.debian.org/tracker/CVE-2020-11612"
]
},
"related_cves": [
{
"value": "CVE-2020-11612",
"evidence": "/upstream"
}
],
"security_relevant": true,
"severity_evidence": "/severity/0/score"
},
"source_id": "core-osv",
"document_id": 451582,
"published_at": "2020-04-07T18:15:13.697+00:00"
}