CVE-2026-58250: CWE-476: NULL Pointer Dereference in nats-io nats-server
NATS Server is a high-performance server for NATS.io, the cloud and edge native messaging system. Prior to 2.12.8 and 2.11.17, an unauthenticated peer with network access to a leafnode listener with compression enabled could crash the server during the pre-authentication leafnode handshake by sending repeated leafnode INFO protocol messages before authentication and account setup completed. This issue is fixed in versions 2.12.8 and 2.11.17.
AI Analysis
Technical Summary
The vulnerability (CWE-476: NULL Pointer Dereference) affects nats-io nats-server versions before 2.12.8 and 2.11.17. It allows an unauthenticated remote attacker with network access to a leafnode listener configured with compression to cause a server crash during the pre-authentication leafnode handshake by sending repeated leafnode INFO protocol messages before authentication and account setup complete. This leads to a denial of service (DoS) condition. The flaw is resolved in versions 2.12.8 and 2.11.17.
Potential Impact
An unauthenticated attacker can cause a denial of service by crashing the nats-server, disrupting messaging services. There is no impact on confidentiality or integrity, only availability is affected.
Mitigation Recommendations
Upgrade nats-server to version 2.12.8 or 2.11.17 or later where the vulnerability is fixed. No other mitigations are specified. Patch status is confirmed by the vendor advisory stating the fix is included in these versions.
CVE-2026-58250: CWE-476: NULL Pointer Dereference 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 2.12.8 and 2.11.17, an unauthenticated peer with network access to a leafnode listener with compression enabled could crash the server during the pre-authentication leafnode handshake by sending repeated leafnode INFO protocol messages before authentication and account setup completed. This issue is fixed in versions 2.12.8 and 2.11.17.
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
The vulnerability (CWE-476: NULL Pointer Dereference) affects nats-io nats-server versions before 2.12.8 and 2.11.17. It allows an unauthenticated remote attacker with network access to a leafnode listener configured with compression to cause a server crash during the pre-authentication leafnode handshake by sending repeated leafnode INFO protocol messages before authentication and account setup complete. This leads to a denial of service (DoS) condition. The flaw is resolved in versions 2.12.8 and 2.11.17.
Potential Impact
An unauthenticated attacker can cause a denial of service by crashing the nats-server, disrupting messaging services. There is no impact on confidentiality or integrity, only availability is affected.
Mitigation Recommendations
Upgrade nats-server to version 2.12.8 or 2.11.17 or later where the vulnerability is fixed. No other mitigations are specified. Patch status is confirmed by the vendor advisory stating the fix is included in these versions.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- GitHub_M
- Date Reserved
- 2026-06-29T21:54:30.330Z
- Cvss Version
- 3.1
- State
- PUBLISHED
- Remediation Level
- null
Threat ID: 6a4eafe7c9d9e3dbe3adea35
Added to database: 07/08/2026, 20:15:35 UTC
Last enriched: 07/16/2026, 10:13:01 UTC
Last updated: 08/22/2026, 12:39:49 UTC
Views: 74
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