NATS Server: MQTT partial CONNECT packets can exhaust pre-auth memory
Summary
| CVE | CVE-2026-58210 |
|---|---|
| State | PUBLISHED |
| Assigner | GitHub_M |
| Source Priority | CVE Program / NVD first with legacy fallback |
| Published | 2026-07-08 20:16:53 UTC |
| Updated | 2026-07-08 20:16:53 UTC |
| Description | 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. |
Risk And Classification
Primary CVSS: v3.1 7.5 HIGH from [email protected]
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Problem Types: CWE-400 | CWE-400 CWE-400: Uncontrolled Resource Consumption
| Version | Source | Type | Score | Severity | Vector |
|---|---|---|---|---|---|
| 3.1 | [email protected] | Secondary | 7.5 | HIGH | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H |
| 3.1 | CNA | DECLARED | 7.5 | HIGH | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H |
CVSS v3.1 Breakdown
Attack Vector
NetworkAttack Complexity
LowPrivileges Required
NoneUser Interaction
NoneScope
UnchangedConfidentiality
NoneIntegrity
NoneAvailability
HighCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Vendor Declared Affected Products
| Source | Vendor | Product | Version | Platforms |
|---|---|---|---|---|
| CNA | Nats-io | Nats-server | affected < 2.12.12 | Not specified |
| CNA | Nats-io | Nats-server | affected >= 2.14.0-RC.1, < 2.14.3 | Not specified |
References
| Reference | Source | Link | Tags |
|---|---|---|---|
| github.com/nats-io/nats-server/commit/e016e47bbf70304945f2ae9dc397e4862a... | [email protected] | github.com | |
| github.com/nats-io/nats-server/releases/tag/v2.12.12 | [email protected] | github.com | |
| github.com/nats-io/nats-server/security/advisories/GHSA-r72h-j7qq-v6qg | [email protected] | github.com | |
| github.com/nats-io/nats-server/commit/bce9ef39469e610aeddb819194ceb7f7ed... | [email protected] | github.com | |
| github.com/nats-io/nats-server/releases/tag/v2.14.3 | [email protected] | github.com | |
| CVE Program record | CVE.ORG | www.cve.org | canonical |
| NVD vulnerability detail | NVD | nvd.nist.gov | canonical, analysis |
No vendor comments have been submitted for this CVE.
There are currently no legacy QID mappings associated with this CVE.