NATS Server: MQTT partial CONNECT packets can exhaust pre-auth memory
NATS Server is a high-performance server for NATS.io, the cloud and edge native messaging system. Prior to 2.14.3 and 2.12.12, an unauthenticated MQTT client could cause the server to retain large incomplete MQTT CONNECT packets before authentication completed, consuming server memory while the parser waited for the advertised MQTT packet length. This issue is fixed in versions 2.14.3 and 2.12.12.
BIT-nats-2026-58210
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:BIT-nats-2026-58210
nats
Source reference: /affected/0/package/name
- Affected versions
- Not stated in this record
- Fixed versions
- 2.12.12
Source reference:
/affected/0/ranges2.14.3Source reference:
/affected/0/ranges - Prerequisites
- Not stated in this record
Structured affected-version data
Original package identities and version rules from this source.
[
{
"ranges": [
{
"type": "SEMVER",
"events": [
{
"introduced": "0"
},
{
"fixed": "2.12.12"
},
{
"introduced": "2.14.0"
},
{
"fixed": "2.14.3"
}
]
}
],
"package": {
"name": "nats",
"purl": "pkg:bitnami/nats",
"ecosystem": "Bitnami"
},
"severity": [
{
"type": "CVSS_V3",
"score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H"
}
],
"database_specific": {
"source": "https://github.com/bitnami/vulndb/tree/main/data/nats/BIT-nats-2026-58210.json"
}
}
]- Related CVEs
- CVE-2026-58210
Source reference:
/aliases
Publisher severity
high
Source reference: /database_specific/severity
- Event
- #25923 · Revision 1
- Added to Heist Feed
- Publisher date