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CVE-2026-58254

Status: AnalyzedMedium (5.3)—

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.

CVSS

Exploitation probability (EPSS)

EPSS (Exploit Prediction Scoring System, FIRST) estimates how likely a vulnerability is to be exploited in the wild within 30 days. It complements CVSS (impact) and CISA KEV (confirmed exploitation).

Affected technologies (1)

Linuxfoundation — Nats-server

CWEs

References

Raw JSON (NVD)

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{
  "id": "CVE-2026-58254",
  "cveTags": [],
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          "version": "2.0.3",
          "timestamp": "2026-07-09T13:38:04.787145Z"
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      "url": "https://github.com/nats-io/nats-server/commit/cbe845932980b71563efac5cfa4cc751c88936cd",
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  "lastModified": "2026-07-13T15:28:33.090",
  "configurations": [
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