CVE-2026-58211

MEDIUMPre-NVD 5.45.4—
EchelonGraph scoreMEDIUM confidence

This medium-severity CVE scores 5.4 under a secondary CVSS source (NVD's own analysis pending). EPSS exploit probability: 0.2%, top 89% of all CVEs by exploit prediction. GitHub Security Advisory data not yet ingested — confidence will rise once GHSA publishes (typical lag: hours to days for open-source ecosystem CVEs; never for infrastructure-only CVEs).

Triggered by: NVD CVSS baseline
Sources: epss, secondary
5.4EG
EchelonGraph verdictMonitorLow exploitation likelihood right now — keep watching.
  • Lower severity and no public exploit yet
CISA-KEV: Not listedEPSS PROB: 0%CVSS: 5.4Exploit: None knownExposed: 0

No vendor fix yet — apply a workaround or compensating control (WAF / firewall / segmentation) and watch for a patch.

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 client could be registered as the configured no_auth_user through a parser path used when the first client operation was not CONNECT, bypassing user-level connection restrictions such as allowed_connection_types or proxy_required that normal authentication would apply. This issue is fixed in versions 2.14.3 and 2.12.12.

CVSS v3
5.4
EG Score
5.4(medium)
EG Risk
24(Track)
EG Risk 24/100SSVC: Track

EG Risk is EchelonGraph's 0–100 priority score: it fuses intrinsic severity with real-world exploitation and automatability so you can rank equal-severity CVEs and fix the most dangerous first. Higher = act sooner. Distinct from the 0–10 EG Score (severity).

How it’s computed
Severity54% × 45%
Exploitation0% × 40%
Automatability0% × 15%
Action: Routine — remediate on your standard cadence.
EPSS PROB
0%
EPSS %ILE
11%
KEV
Not listed

Published

July 8, 2026

Last Modified

July 9, 2026

Advisory Details (1)

Auto-updated Jul 8, 2026
Patch available. Sources: github.
github Patch Available

`no_auth_user` pre-CONNECT fast path bypasses user connection restrictions · Advisory · nats-io/nats-server · GitHub

Affected: v2.14.3 and v2.12.12.

https://github.com/nats-io/nats-server/security/advisories/GHSA-hmmp-q8cx-v964

Weakness Classification(1)

MITRE Common Weakness Enumeration — the root-cause categories this CVE belongs to.

Data Freshness Timeline

(refreshed 15× in last 7d / 42× in last 30d)

Each row is a source pipeline that fetched or updated this CVE on that date, with what changed. For example, "NVD update" means NVD published or revised its analysis for this CVE; "MITRE cvelistV5" means we ingested or refreshed it from the CNA feed. Most recent first.

  1. 2026-07-30 23:04 UTCEG score recompute
  2. 2026-07-30 16:28 UTCEPSS rescore
  3. 2026-07-30 01:30 UTCEPSS rescore
  4. 2026-07-30 01:30 UTCEPSS rescore
  5. 2026-07-28 17:29 UTCEG score recompute
  6. 2026-07-28 15:37 UTCEPSS rescore
  7. 2026-07-27 15:38 UTCEG score recompute
  8. 2026-07-27 14:14 UTCEPSS rescore
  9. 2026-07-26 14:54 UTCEPSS rescore
  10. 2026-07-26 14:54 UTCEPSS rescore
  11. 2026-07-26 12:25 UTCEG score recompute
  12. 2026-07-25 14:18 UTCEPSS rescore
  13. 2026-07-25 14:18 UTCEPSS rescore
  14. 2026-07-24 14:18 UTCEPSS rescore
  15. 2026-07-24 14:18 UTCEPSS rescore
  16. 2026-07-23 14:18 UTCEPSS rescore
  17. 2026-07-23 14:18 UTCEPSS rescore
  18. 2026-07-23 03:20 UTCEG score recompute
  19. 2026-07-22 14:08 UTCEPSS rescore
  20. 2026-07-22 14:08 UTCEPSS rescore
  21. 2026-07-21 15:25 UTCEPSS rescore
  22. 2026-07-21 15:25 UTCEPSS rescore
  23. 2026-07-20 17:08 UTCEPSS rescore
  24. 2026-07-19 14:31 UTCEPSS rescore
  25. 2026-07-19 14:31 UTCEPSS rescore
Show 17 more
  1. 2026-07-19 02:29 UTCEPSS rescore
  2. 2026-07-18 10:04 UTCEPSS rescore
  3. 2026-07-16 17:03 UTCEPSS rescore
  4. 2026-07-15 16:57 UTCEPSS rescore
  5. 2026-07-15 16:57 UTCEPSS rescore
  6. 2026-07-15 02:00 UTCEPSS rescore
  7. 2026-07-15 02:00 UTCEPSS rescore
  8. 2026-07-13 22:31 UTCEPSS rescore
  9. 2026-07-13 06:13 UTCEPSS rescore
  10. 2026-07-13 06:13 UTCEPSS rescore
  11. 2026-07-12 05:46 UTCEPSS rescore
  12. 2026-07-11 08:27 UTCEPSS rescore
  13. 2026-07-11 08:27 UTCEPSS rescore
  14. 2026-07-09 19:10 UTCEPSS rescore
  15. 2026-07-09 19:10 UTCEPSS rescore
  16. 2026-07-08 20:44 UTCEG score recompute
  17. 2026-07-08 20:44 UTCMITRE cvelistV5first tracked

Frequently asked(5)

What is CVE-2026-58211?
CVE-2026-58211 is a medium vulnerability published on July 8, 2026. 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 client could be registered as the configured noauthuser through a parser path used when the first client operation was not CONNECT, bypassing user-level connection…
When was CVE-2026-58211 disclosed?
CVE-2026-58211 was first published in the National Vulnerability Database on July 8, 2026, with the most recent update on July 9, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2026-58211 actively exploited?
CVE-2026-58211 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 0% probability of exploitation in the next 30 days, which ranks it in the top 89.0% of all scored CVEs.
What is the CVSS score of CVE-2026-58211?
CVE-2026-58211 has a CVSS v3 base score of 5.4 (NVD).
How do I remediate CVE-2026-58211?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2026-58211, EchelonGraph cross-links them in the Vendor Advisories panel below — those typically contain the canonical remediation steps, fixed version numbers, and any vendor-specific mitigations.

Dependency Blast Radius

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