DEBIAN-CVE-2026-44248
Netty is an asynchronous, event-driven network application framework. Prior to 4.2.13.Final and 4.1.133.Final, the MQTT 5 header Properties section is parsed and buffered before any message size limit is applied. Specifically, in MqttDecoder, the decodeVariableHeader() method is called before the bytesRemainingBeforeVariableHeader > maxBytesInMessage check. The decodeVariableHeader() can call other methods which will call decodeProperties(). Effectively, Netty does not apply any limits to the size of the properties being decoded. Additionally, because MqttDecoder extends ReplayingDecoder, Netty will repeatedly re-parse the enormous Properties sections and buffer the bytes in memory, until the entire thing parses to completion. This can cause high resource usage in both CPU and memory. This vulnerability is fixed in 4.2.13.Final and 4.1.133.Final.
DEBIAN-CVE-2026-44248
Primary source · Revision 1
Imported from structured advisory data. Source references identify upstream records or fields; verify affected versions and your deployed configuration.
Security context
Source reference: osv:DEBIAN-CVE-2026-44248
netty
Source reference: /affected/0/package/name
- Affected versions
- 1:4.1.48-10
Source reference:
/affected/0/versions1:4.1.48-11Source reference:
/affected/0/versions1:4.1.48-12Source reference:
/affected/0/versions1:4.1.48-13Source reference:
/affected/0/versions1:4.1.48-14Source reference:
/affected/0/versions1:4.1.48-15Source reference:
/affected/0/versions1:4.1.48-16Source reference:
/affected/0/versions1:4.1.48-7Source reference:
/affected/0/versions1:4.1.48-7+deb12u1Source reference:
/affected/0/versions1:4.1.48-7+deb12u2Source reference:
/affected/0/versions1:4.1.48-8Source reference:
/affected/0/versions1:4.1.48-9Source reference:
/affected/0/versions - Fixed versions
- Not stated in this record
- Prerequisites
- Not stated in this record
netty
Source reference: /affected/1/package/name
- Affected versions
- 1:4.1.48-10
Source reference:
/affected/1/versions1:4.1.48-10+deb13u1Source reference:
/affected/1/versions1:4.1.48-11Source reference:
/affected/1/versions1:4.1.48-12Source reference:
/affected/1/versions1:4.1.48-13Source reference:
/affected/1/versions1:4.1.48-14Source reference:
/affected/1/versions1:4.1.48-15Source reference:
/affected/1/versions1:4.1.48-16Source reference:
/affected/1/versions - Fixed versions
- Not stated in this record
- Prerequisites
- Not stated in this record
netty
Source reference: /affected/2/package/name
- Affected versions
- 1:4.1.48-10
Source reference:
/affected/2/versions1:4.1.48-11Source reference:
/affected/2/versions1:4.1.48-12Source reference:
/affected/2/versions1:4.1.48-13Source reference:
/affected/2/versions1:4.1.48-14Source reference:
/affected/2/versions1:4.1.48-15Source reference:
/affected/2/versions1:4.1.48-16Source reference:
/affected/2/versions - Fixed versions
- Not stated in this record
- Prerequisites
- Not stated in this record
Structured affected-version data
Original package identities and version rules from this source.
[
{
"ranges": [
{
"type": "ECOSYSTEM",
"events": [
{
"introduced": "0"
}
]
}
],
"package": {
"name": "netty",
"purl": "pkg:deb/debian/netty?arch=source&distro=bookworm",
"ecosystem": "Debian:12"
},
"versions": [
"1:4.1.48-10",
"1:4.1.48-11",
"1:4.1.48-12",
"1:4.1.48-13",
"1:4.1.48-14",
"1:4.1.48-15",
"1:4.1.48-16",
"1:4.1.48-7",
"1:4.1.48-7+deb12u1",
"1:4.1.48-7+deb12u2",
"1:4.1.48-8",
"1:4.1.48-9"
],
"database_specific": {
"source": "https://storage.googleapis.com/debian-osv/debian-cve-osv/DEBIAN-CVE-2026-44248.json"
},
"ecosystem_specific": {
"urgency": "not yet assigned"
}
},
{
"ranges": [
{
"type": "ECOSYSTEM",
"events": [
{
"introduced": "0"
}
]
}
],
"package": {
"name": "netty",
"purl": "pkg:deb/debian/netty?arch=source&distro=trixie",
"ecosystem": "Debian:13"
},
"versions": [
"1:4.1.48-10",
"1:4.1.48-10+deb13u1",
"1:4.1.48-11",
"1:4.1.48-12",
"1:4.1.48-13",
"1:4.1.48-14",
"1:4.1.48-15",
"1:4.1.48-16"
],
"database_specific": {
"source": "https://storage.googleapis.com/debian-osv/debian-cve-osv/DEBIAN-CVE-2026-44248.json"
},
"ecosystem_specific": {
"urgency": "not yet assigned"
}
},
{
"ranges": [
{
"type": "ECOSYSTEM",
"events": [
{
"introduced": "0"
}
]
}
],
"package": {
"name": "netty",
"purl": "pkg:deb/debian/netty?arch=source&distro=forky",
"ecosystem": "Debian:14"
},
"versions": [
"1:4.1.48-10",
"1:4.1.48-11",
"1:4.1.48-12",
"1:4.1.48-13",
"1:4.1.48-14",
"1:4.1.48-15",
"1:4.1.48-16"
],
"database_specific": {
"source": "https://storage.googleapis.com/debian-osv/debian-cve-osv/DEBIAN-CVE-2026-44248.json"
},
"ecosystem_specific": {
"urgency": "not yet assigned"
}
}
]Publisher severity
No explicit severity was provided.
- Event
- #57052 · Revision 1
- Added to Heist Feed
- Publisher date