CVE-2026-58210: CWE-400: Uncontrolled Resource Consumption in nats-io nats-server
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.
AI Analysis
Technical Summary
CVE-2026-58210 describes an uncontrolled resource consumption vulnerability (CWE-400) in nats-io nats-server. Specifically, before versions 2.12.12 and 2.14.3, an unauthenticated MQTT client can send incomplete MQTT CONNECT packets that cause the server to retain large amounts of memory while waiting for the full packet to arrive. This can degrade server availability by exhausting memory resources. The vulnerability is addressed by fixes in nats-server versions 2.12.12 and 2.14.3.
Potential Impact
An unauthenticated attacker can cause a denial of service condition by consuming excessive server memory, potentially impacting availability. There is no impact on confidentiality or integrity according to the CVSS vector. The CVSS score is 7.5 (high severity) reflecting the availability impact with no privileges or user interaction required.
Mitigation Recommendations
Upgrade affected nats-server instances to version 2.12.12 or later, or 2.14.3 or later, where this vulnerability is fixed. No other mitigation or workaround is indicated. Patch status is confirmed fixed in these versions.
CVE-2026-58210: CWE-400: Uncontrolled Resource Consumption in nats-io nats-server
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.
CVSS v3.1
Score 7.5high
Affected software
pkg:github/nats-io/nats-serverRun on your own infrastructure? Check whether these packages are installed with threat-finder — our free open-source scanner.
Weaknesses
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
CVE-2026-58210 describes an uncontrolled resource consumption vulnerability (CWE-400) in nats-io nats-server. Specifically, before versions 2.12.12 and 2.14.3, an unauthenticated MQTT client can send incomplete MQTT CONNECT packets that cause the server to retain large amounts of memory while waiting for the full packet to arrive. This can degrade server availability by exhausting memory resources. The vulnerability is addressed by fixes in nats-server versions 2.12.12 and 2.14.3.
Potential Impact
An unauthenticated attacker can cause a denial of service condition by consuming excessive server memory, potentially impacting availability. There is no impact on confidentiality or integrity according to the CVSS vector. The CVSS score is 7.5 (high severity) reflecting the availability impact with no privileges or user interaction required.
Mitigation Recommendations
Upgrade affected nats-server instances to version 2.12.12 or later, or 2.14.3 or later, where this vulnerability is fixed. No other mitigation or workaround is indicated. Patch status is confirmed fixed in these versions.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- GitHub_M
- Date Reserved
- 2026-06-29T17:09:25.872Z
- Cvss Version
- 3.1
- State
- PUBLISHED
- Remediation Level
- null
Threat ID: 6a4eafe7c9d9e3dbe3adea1b
Added to database: 07/08/2026, 20:15:35 UTC
Last enriched: 07/16/2026, 10:12:34 UTC
Last updated: 08/22/2026, 10:52:10 UTC
Views: 59
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