NATS Server: Incomplete fix for CVE-2026-33249: Leaf node connections bypass Nats-Trace-Dest permission check
NATS Server is a high-performance server for NATS.io, the cloud and edge native messaging system. Prior to 2.14.3 and 2.12.8, message trace destination checks were applied to ordinary client connections but not consistently to messages arriving through leafnode connections, allowing a leafnode operator to send trace events to subjects that would not otherwise be permitted and to use trace-only behavior to prevent normal delivery or storage of affected messages. This issue is fixed in versions 2.14.3 and 2.12.8.
BIT-nats-2026-58254
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-2026-58254
nats
Source reference: /affected/0/package/name
- Affected versions
- Not stated in this record
- Fixed versions
- 2.12.8
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": "2.12.8"
},
{
"introduced": "2.14.0"
},
{
"fixed": "2.14.3"
}
]
}
],
"package": {
"name": "nats",
"purl": "pkg:bitnami/nats",
"ecosystem": "Bitnami"
},
"severity": [
{
"type": "CVSS_V4",
"score": "CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:L/VI:L/VA:L/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X"
}
],
"database_specific": {
"source": "https://github.com/bitnami/vulndb/tree/main/data/nats/BIT-nats-2026-58254.json"
}
}
]- Related CVEs
- CVE-2026-58254
Source reference:
/aliases
Publisher severity
medium
Source reference: /database_specific/severity
- Event
- #25936 · Revision 1
- Added to Heist Feed
- Publisher date