High
nats-server — security advisory
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, a WebSocket listener could route requests for the MQTT-over-WebSocket path into MQTT handling even when MQTT was not configured, allowing an unauthenticated client with access to the WebSocket listener to reach uninitialized MQTT state and crash the server process. This issue is fixed in versions 2.14.3 and 2.12.12.
- Products
- nats-server
- Affected versions
- 2.10.24-1, 2.10.27-1, 2.10.27-1build1, 2.10.27-1ubuntu0.26.04.1~esm1, 2.10.3-1, 2.10.4-1, 2.10.7-1, 2.10.7-1ubuntu0.1, 2.10.7-1ubuntu0.2, 2.10.7-1ubuntu0.3, 2.14.1-1, 2.14.3-1, 2.9.19-1build1
- Fixed versions
- Not specified
- CVEs
- CVE-2026-58208
- Confirmed fixed CVEs
- Not specified
- Updated in this feed
- 31 Oct 2026, 02:48 UTC · Revision 1
Source evidence
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, a WebSocket listener could route requests for the MQTT-over-WebSocket path into MQTT handling even when MQTT was not configured, allowing an unauthenticated client with access to the WebSocket listener to reach uninitialized MQTT state and crash the server process. This issue is fixed in versions 2.14.3 and 2.12.12.
osv:UBUNTU-CVE-2026-58208
nats-server
Fixed versions: Not specified
nats-server
Fixed versions: Not specified
nats-server
Fixed versions: Not specified
nats-server
Fixed versions: Not specified
Complete source record
{
"id": "ecae0b076602d12a429905f96f4ad462e4cbae924bc877dc5a2fa137b706d1f1",
"url": "https://osv.dev/vulnerability/UBUNTU-CVE-2026-58208",
"method": "structured",
"payload": {
"kind": "advisory",
"title": "UBUNTU-CVE-2026-58208",
"summary": "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, a WebSocket listener could route requests for the MQTT-over-WebSocket path into MQTT handling even when MQTT was not configured, allowing an unauthenticated client with access to the WebSocket listener to reach uninitialized MQTT state and crash the server process. This issue is fixed in versions 2.14.3 and 2.12.12.",
"evidence": "osv:UBUNTU-CVE-2026-58208",
"products": [
{
"name": {
"value": "nats-server",
"evidence": "/affected/0/package/name"
},
"prerequisites": [],
"fixed_versions": [],
"affected_versions": [
{
"value": "2.9.19-1build1",
"evidence": "/affected/0/versions"
},
{
"value": "2.10.3-1",
"evidence": "/affected/0/versions"
},
{
"value": "2.10.4-1",
"evidence": "/affected/0/versions"
},
{
"value": "2.10.7-1",
"evidence": "/affected/0/versions"
},
{
"value": "2.10.7-1ubuntu0.1",
"evidence": "/affected/0/versions"
},
{
"value": "2.10.7-1ubuntu0.2",
"evidence": "/affected/0/versions"
},
{
"value": "2.10.7-1ubuntu0.3",
"evidence": "/affected/0/versions"
}
]
},
{
"name": {
"value": "nats-server",
"evidence": "/affected/1/package/name"
},
"prerequisites": [],
"fixed_versions": [],
"affected_versions": [
{
"value": "2.10.24-1",
"evidence": "/affected/1/versions"
},
{
"value": "2.10.27-1",
"evidence": "/affected/1/versions"
}
]
},
{
"name": {
"value": "nats-server",
"evidence": "/affected/2/package/name"
},
"prerequisites": [],
"fixed_versions": [],
"affected_versions": [
{
"value": "2.10.27-1build1",
"evidence": "/affected/2/versions"
},
{
"value": "2.14.1-1",
"evidence": "/affected/2/versions"
},
{
"value": "2.14.3-1",
"evidence": "/affected/2/versions"
}
]
},
{
"name": {
"value": "nats-server",
"evidence": "/affected/3/package/name"
},
"prerequisites": [],
"fixed_versions": [],
"affected_versions": [
{
"value": "2.10.27-1",
"evidence": "/affected/3/versions"
},
{
"value": "2.10.27-1build1",
"evidence": "/affected/3/versions"
},
{
"value": "2.10.27-1ubuntu0.26.04.1~esm1",
"evidence": "/affected/3/versions"
}
]
}
],
"severity": "high",
"structured": {
"id": "UBUNTU-CVE-2026-58208",
"aliases": [
"UBUNTU-CVE-2026-58208"
],
"metrics": [
{
"type": "CVSS_V3",
"score": "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:N/I:N/A:H"
},
{
"type": "CVSS_V3",
"score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H"
},
{
"type": "Ubuntu",
"score": "medium"
}
],
"affected": [
{
"ranges": [
{
"type": "ECOSYSTEM",
"events": [
{
"introduced": "0"
}
]
}
],
"package": {
"name": "nats-server",
"purl": "pkg:deb/ubuntu/nats-server?arch=source&distro=noble",
"ecosystem": "Ubuntu:24.04:LTS"
},
"versions": [
"2.9.19-1build1",
"2.10.3-1",
"2.10.4-1",
"2.10.7-1",
"2.10.7-1ubuntu0.1",
"2.10.7-1ubuntu0.2",
"2.10.7-1ubuntu0.3"
],
"database_specific": {
"source": "https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-58208.json"
},
"ecosystem_specific": {
"binaries": [
{
"binary_name": "golang-github-nats-io-nats-server-dev",
"binary_version": "2.10.7-1ubuntu0.3"
},
{
"binary_name": "nats-server",
"binary_version": "2.10.7-1ubuntu0.3"
}
]
}
},
{
"ranges": [
{
"type": "ECOSYSTEM",
"events": [
{
"introduced": "0"
}
]
}
],
"package": {
"name": "nats-server",
"purl": "pkg:deb/ubuntu/nats-server?arch=source&distro=questing",
"ecosystem": "Ubuntu:25.10"
},
"versions": [
"2.10.24-1",
"2.10.27-1"
],
"database_specific": {
"source": "https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-58208.json"
},
"ecosystem_specific": {
"binaries": [
{
"binary_name": "golang-github-nats-io-nats-server-dev",
"binary_version": "2.10.27-1"
},
{
"binary_name": "nats-server",
"binary_version": "2.10.27-1"
}
]
}
},
{
"ranges": [
{
"type": "ECOSYSTEM",
"events": [
{
"introduced": "0"
}
]
}
],
"package": {
"name": "nats-server",
"purl": "pkg:deb/ubuntu/nats-server?arch=source&distro=stonking",
"ecosystem": "Ubuntu:26.10"
},
"versions": [
"2.10.27-1build1",
"2.14.1-1",
"2.14.3-1"
],
"database_specific": {
"source": "https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-58208.json"
},
"ecosystem_specific": {
"binaries": [
{
"binary_name": "golang-github-nats-io-nats-server-dev",
"binary_version": "2.14.3-1"
},
{
"binary_name": "nats-server",
"binary_version": "2.14.3-1"
}
]
}
},
{
"ranges": [
{
"type": "ECOSYSTEM",
"events": [
{
"introduced": "0"
}
]
}
],
"package": {
"name": "nats-server",
"purl": "pkg:deb/ubuntu/nats-server?arch=source&distro=esm-apps%2Fresolute",
"ecosystem": "Ubuntu:Pro:26.04:LTS"
},
"versions": [
"2.10.27-1",
"2.10.27-1build1",
"2.10.27-1ubuntu0.26.04.1~esm1"
],
"database_specific": {
"source": "https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-58208.json"
},
"ecosystem_specific": {
"binaries": [
{
"binary_name": "golang-github-nats-io-nats-server-dev",
"binary_version": "2.10.27-1ubuntu0.26.04.1~esm1"
},
{
"binary_name": "nats-server",
"binary_version": "2.10.27-1ubuntu0.26.04.1~esm1"
}
]
}
}
],
"modified": "2026-10-17T12:59:13.501065839Z",
"provider": "osv",
"upstream": [
"CVE-2026-58208"
],
"references": [
"https://ubuntu.com/security/CVE-2026-58208",
"https://www.cve.org/CVERecord?id=CVE-2026-58208",
"https://github.com/nats-io/nats-server/security/advisories/GHSA-p957-7v2w-g93g"
]
},
"related_cves": [
{
"value": "CVE-2026-58208",
"evidence": "/upstream"
}
],
"security_relevant": true,
"severity_evidence": "/severity/1/score"
},
"source_id": "core-osv",
"document_id": 359468,
"published_at": "2026-07-08T21:16:00+00:00"
}