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 WebSocket listener could route requests for the MQTT-over-WebSocket path into MQTT handling even when MQTT was not configured, allowing an unauthenticated client with access to the WebSocket listener to reach uninitialized MQTT state and crash the server process. This issue is fixed in versions 2.14.3 and 2.12.12.
CVE-2026-58208
“—” beside the score: it is equal to NVD's CVSS score.
This high-severity CVE scores 7.5 under NVD CVSS v3. EPSS exploit probability: 0.6% (48th percentile of EPSS-scored CVEs). No GitHub Security Advisory CVSS is on record for this CVE.
Also known asEUVD-2026-42391 (ENISA EUVD)Source: ENISA EUVD
- High severity, but no confirmed exploitation yet
A fix is available — apply it.
- CVSS v3
- 7.5
- EG Score
- 7.5HIGHmedium confidence
- EG Risk
- 34EG Risk 34/100
EG Risk is EchelonGraph's 0–100 priority score. It fuses impact severity (EG Severity, the CVSS base score, never the KEV-floored or EPSS-lifted EG Score) with real-world exploitation and automatability, under weights EchelonGraph set by hand, so you can rank equal-severity CVEs and fix the most dangerous first. Higher = act sooner.
How it’s computed (value × EchelonGraph’s weight)Severity75% × 45%Impact severity (EG Severity): CVSS 7.5 of 10. Never the KEV-floored or EPSS-lifted EG Score.Exploitation0.6% × 40%FIRST EPSS: the 30-day exploitation probability when EchelonGraph scored this CVE.Automatability0% × 15%CISA's SSVC Automatable value: no (Vulnrichment).SSVC (CISA's decision table, applied by EchelonGraph): Track at every mission impact level.Exploitation none (CISA Vulnrichment) · Automatable no (CISA Vulnrichment) · Technical impact partial (CISA Vulnrichment). All three are CISA's SSVC values (Vulnrichment). EchelonGraph applied CISA's decision table to them; CISA publishes SSVC inputs and the table, not a decision for each CVE.Action: A fix is available. Apply it within your standard update timelines. - EPSS PROB
- 0.6%
- EPSS %ILE
- 48th
- KEV
- Not listed
What the EG score is made of (scorer v4.0: the three questions the 0–10 score mixes, published apart · methodology)
The EG score (7.5): severity, escalated by confirmed exploitation. This CVE's 7.5 is its impact severity (EG Severity), not escalated.
- EG Severity
- 7.5 HIGHCVSS-B, impact only: no KEV listing, EPSS or EG-KEV tier raises it.NVD CVSS v3 · CVSS v3.0 or v3.1
- EG Likelihood
- 0.6% within 30 daysSource: FIRST EPSS (model v2026.06.15, score date 2026-11-01). FIRST's exploitation probability, not an EchelonGraph model.
- Confirmed exploitation
- None on record (CISA KEV, EG-KEV Tier 1)Reported apart from the likelihood: an observed fact, not a probability.
- EG Priority
- SSVC Track at medium mission impactTrack at every mission impact level.CISA BOD 26-04: 60 days if the affected system is publicly exposed; Fix on system upgrade if it is not.Each input and its source, and whom BOD 26-04 binds: the SSVC and BOD 26-04 blocks below.
SSVC (CISA's decision table, applied by EchelonGraph)Track at every mission impact level.
A fix is available. Apply it within your standard update timelines.
Exploitation none (CISA Vulnrichment) · Automatable no (CISA Vulnrichment) · Technical impact partial (CISA Vulnrichment). All three are CISA's SSVC values (Vulnrichment). EchelonGraph applied CISA's decision table to them; CISA publishes SSVC inputs and the table, not a decision for each CVE. Mission impact is CISA's Mission & Well-being decision point, and only you can judge it. CISA's table makes it high when Mission Prevalence is Essential — the vulnerable component "directly provides capabilities that constitute at least one MEF for at least one entity" (MEF: mission essential function) — or when Public Well-Being Impact is Irreversible: "multiple fatalities are likely", the cyber-physical system "is likely lost or destroyed", "extreme or serious externalities" are imposed on other parties, or social systems such as elections or the financial grid "are destabilized and potentially collapse". CISA's decision table
BOD 26-04 (CISA's remediation timeline, Table 1)60 days if the affected system is publicly exposed; Fix on system upgrade if it is not.
The score's inputs: In CISA KEV no (CISA's KEV catalog) · Automatable no (CISA Vulnrichment) · Technical impact partial (CISA Vulnrichment). Whether your system is publicly exposed is yours to answer. BOD 26-04 binds US Federal Civilian Executive Branch agencies; for anyone else it is CISA's published timeline, a reference rather than an obligation. The directive · how EchelonGraph applies it
Published
July 8, 2026
Last Modified
October 25, 2026
Advisory Details (5)
Auto-updated Jul 8, 2026Release v2.14.3
Patch available: nats-io/nats-server v2.14.3
https://github.com/nats-io/nats-server/releases/tag/v2.14.3Release v2.12.12
Patch available: nats-io/nats-server v2.12.12
https://github.com/nats-io/nats-server/releases/tag/v2.12.12commit 837536b98b3a (nats-io/nats-server)
Fix landed in nats-io/nats-server commit 837536b98b3a — awaiting tagged release
https://github.com/nats-io/nats-server/commit/837536b98b3a9280b993282155ff2bdd3ca38c30commit 73b3dd9a5ea0 (nats-io/nats-server)
Fix landed in nats-io/nats-server commit 73b3dd9a5ea0 — awaiting tagged release
https://github.com/nats-io/nats-server/commit/73b3dd9a5ea0fa7bf08b702338676355b29b5fb4MQTT-over-WebSocket Path Can Crash WebSocket-Only JetStream Servers Before MQTT Is Enabled · Advisory · nats-io/nats-server · GitHub
Affected: v2.14.3 and v2.12.12.
https://github.com/nats-io/nats-server/security/advisories/GHSA-p957-7v2w-g93gVendor Advisories for CVE-2026-58208(1)
These vendors published their own advisory mentioning this CVE — often with vendor-specific remediation steps + affected product lists not in NVD.
Affected Packages
(3 across 3 ecosystems)
Debian:12(1)
| Package | Vulnerable range | Fix by version range | Dependents |
|---|---|---|---|
| nats-server | 2.10.1-1 ... 2.9.19-1 (15 versions) |
| — |
Debian:13(1)
| Package | Vulnerable range | Fix by version range | Dependents |
|---|---|---|---|
| nats-server | 2.10.27-1 ... 2.14.6-1 (6 versions) |
| — |
Debian:14(1)
| Package | Vulnerable range | Fix by version range | Dependents |
|---|---|---|---|
| nats-server | 2.10.27-1, 2.12.4-1, 2.12.6-1, 2.14.1-1 |
| — |
Weakness Classification(1)
MITRE Common Weakness Enumeration — the root-cause categories this CVE belongs to.
Data Freshness Timeline
(refreshed 9× in last 7d / 43× in last 30d)
Each row is a time one of our pipelines fetched, updated or re-scored this CVE. 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. An arrow marks a change the record states ("CVSS v3 → 9.1"); EPSS and GHSA rows show the values recorded at that time, not what changed (EPSS values are rounded; hover one for the exact figures). Most recent first.
Showing the most recent 100 of 251 refreshes on record for this CVE.
A repeat, a row identical to one the same pipeline wrote less than 10 seconds earlier, is not a separate refresh and is not counted. None are among the latest 100 rows. The 151 oldest rows on record are not shown and were not checked, so the counts can still include repeats.
- 2026-11-02 16:45 UTCEPSS rescoreEPSS 0.6% · 48th percentile
- 2026-11-01 17:24 UTCEG score recompute
- 2026-11-01 17:24 UTCVendor advisory
- 2026-11-01 16:35 UTCEPSS rescoreEPSS 0.6% · 48th percentile
- 2026-10-31 16:33 UTCEPSS rescoreEPSS 0.6% · 48th percentile
- 2026-10-30 16:34 UTCEPSS rescoreEPSS 0.6% · 48th percentile
- 2026-10-29 16:33 UTCEPSS rescoreEPSS 0.6% · 48th percentile
- 2026-10-28 16:32 UTCEPSS rescoreEPSS 0.6% · 48th percentile
- 2026-10-27 16:32 UTCEPSS rescoreEPSS 0.6% · 48th percentile
- 2026-10-26 16:31 UTCEPSS rescoreEPSS 0.6% · 48th percentile
- 2026-10-25 17:28 UTCEG score recompute
- 2026-10-25 17:28 UTCVendor advisory
- 2026-10-25 16:33 UTCEPSS rescoreEPSS 0.6% · 48th percentile
- 2026-10-25 14:16 UTCEG score recompute
- 2026-10-24 16:33 UTCEPSS rescoreEPSS 0.6% · 48th percentile
- 2026-10-23 16:32 UTCEPSS rescoreEPSS 0.6% · 48th percentile
- 2026-10-23 13:05 UTCEG score recompute
- 2026-10-23 13:05 UTCVendor advisory
- 2026-10-22 16:34 UTCEPSS rescoreEPSS 0.6% · 48th percentile
- 2026-10-21 16:33 UTCEPSS rescoreEPSS 0.6% · 47th percentile
- 2026-10-20 16:33 UTCEPSS rescoreEPSS 0.6% · 47th percentile
- 2026-10-19 16:32 UTCEPSS rescoreEPSS 0.6% · 47th percentile
- 2026-10-18 16:32 UTCEPSS rescoreEPSS 0.6% · 47th percentile
- 2026-10-18 03:28 UTCEG score recompute
- 2026-10-17 16:35 UTCEPSS rescoreEPSS 0.6% · 47th percentile
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- 2026-10-16 16:43 UTCEPSS rescoreEPSS 0.6% · 47th percentile
- 2026-10-16 13:07 UTCEG score recompute
- 2026-10-15 16:32 UTCEPSS rescoreEPSS 0.6% · 47th percentile
- 2026-10-14 16:33 UTCEPSS rescoreEPSS 0.6% · 47th percentile
- 2026-10-13 16:34 UTCEPSS rescoreEPSS 0.6% · 47th percentile
- 2026-10-12 16:34 UTCEPSS rescoreEPSS 0.6% · 47th percentile
- 2026-10-12 15:53 UTCEG score recompute
- 2026-10-11 19:36 UTCEG score recompute
- 2026-10-11 16:52 UTCEG score recompute
- 2026-10-11 14:14 UTCEG score recompute
- 2026-10-11 13:49 UTCEPSS rescoreEPSS 0.6% · 47th percentile
- 2026-10-10 20:00 UTCEPSS rescoreEPSS 0.6% · 47th percentile
- 2026-10-09 20:07 UTCEPSS rescoreEPSS 0.6% · 47th percentile
- 2026-10-08 17:13 UTCEPSS rescoreEPSS 0.6% · 47th percentile
- 2026-10-07 23:48 UTCEPSS rescoreEPSS 0.6% · 47th percentile
- 2026-10-06 15:18 UTCEPSS rescoreEPSS 0.6% · 46th percentile
- 2026-10-05 17:43 UTCEPSS rescoreEPSS 0.6% · 46th percentile
- 2026-10-04 23:22 UTCEPSS rescoreEPSS 0.6% · 46th percentile
- 2026-10-03 14:26 UTCEPSS rescoreEPSS 0.6% · 46th percentile
- 2026-10-02 17:56 UTCEPSS rescoreEPSS 0.6% · 46th percentile
- 2026-10-01 19:50 UTCEPSS rescoreEPSS 0.6% · 46th percentile
- 2026-10-01 16:10 UTCEG score recompute
- 2026-10-01 16:10 UTCVendor advisory
- 2026-09-30 15:03 UTCEPSS rescoreEPSS 0.6% · 46th percentile
- 2026-09-29 15:22 UTCEPSS rescoreEPSS 0.6% · 46th percentile
- 2026-09-28 13:51 UTCEPSS rescoreEPSS 0.6% · 46th percentile
- 2026-09-28 13:21 UTCEG score recompute
- 2026-09-28 13:21 UTCVendor advisory
- 2026-09-27 13:48 UTCEPSS rescoreEPSS 0.6% · 46th percentile
- 2026-09-26 15:59 UTCEPSS rescoreEPSS 0.6% · 46th percentile
- 2026-09-24 14:04 UTCEPSS rescoreEPSS 0.6% · 46th percentile
- 2026-09-24 11:47 UTCEG score recompute
- 2026-09-24 11:47 UTCVendor advisory
- 2026-09-23 17:54 UTCEPSS rescoreEPSS 0.6% · 47th percentile
- 2026-09-23 06:05 UTCEG score recompute
- 2026-09-23 06:05 UTCVendor advisory
- 2026-09-18 19:28 UTCEPSS rescoreEPSS 0.6% · 47th percentile
- 2026-09-18 05:42 UTCEG score recompute
- 2026-09-18 05:42 UTCVendor advisory
- 2026-09-17 19:31 UTCEPSS rescoreEPSS 0.6% · 47th percentile
- 2026-09-16 14:08 UTCEPSS rescoreEPSS 0.6% · 47th percentile
- 2026-09-16 05:15 UTCEPSS rescoreEPSS 0.6% · 46th percentile
- 2026-09-15 03:11 UTCEPSS rescoreEPSS 0.6% · 46th percentile
- 2026-09-14 11:18 UTCVendor advisory
- 2026-09-13 23:48 UTCEG score recompute
- 2026-09-13 23:48 UTCVendor advisory
- 2026-09-13 16:47 UTCEPSS rescoreEPSS 0.6% · 46th percentile
- 2026-09-13 08:23 UTCEG score recompute
- 2026-09-13 08:23 UTCVendor advisory
- 2026-09-12 15:01 UTCVendor advisory
- 2026-09-12 03:31 UTCEG score recompute
- 2026-09-12 03:31 UTCVendor advisory
- 2026-09-11 14:53 UTCEPSS rescoreEPSS 0.6% · 46th percentile
- 2026-09-10 09:35 UTCEPSS rescoreEPSS 0.6% · 46th percentile
- 2026-09-08 22:01 UTCEPSS rescoreEPSS 0.6% · 46th percentile
- 2026-09-07 16:01 UTCEPSS rescoreEPSS 0.6% · 46th percentile
- 2026-09-06 14:02 UTCEG score recompute
- 2026-09-06 14:02 UTCVendor advisory
- 2026-09-06 13:47 UTCEPSS rescoreEPSS 0.6% · 46th percentile
- 2026-09-05 22:46 UTCEG score recompute
- 2026-09-05 22:46 UTCVendor advisory
- 2026-09-04 05:07 UTCEPSS rescoreEPSS 0.6% · 46th percentile
- 2026-09-02 14:12 UTCEPSS rescoreEPSS 0.6% · 46th percentile
- 2026-09-01 13:54 UTCEPSS rescoreEPSS 0.6% · 46th percentile
- 2026-09-01 04:40 UTCEPSS rescoreEPSS 0.6% · 46th percentile
- 2026-08-30 19:17 UTCEPSS rescoreEPSS 0.6% · 46th percentile
- 2026-08-30 18:58 UTCVendor advisory
- 2026-08-30 07:28 UTCEG score recompute
- 2026-08-30 07:28 UTCVendor advisory
- 2026-08-30 01:22 UTCEPSS rescoreEPSS 0.6% · 46th percentile
- 2026-08-28 21:42 UTCEPSS rescoreEPSS 0.6% · 46th percentile
- 2026-08-27 21:49 UTCEG score recompute
- 2026-08-27 21:49 UTCVendor advisory
- 2026-08-27 14:25 UTCEPSS rescoreEPSS 0.6% · 46th percentile
- 2026-08-27 01:26 UTCEG score recompute
Related CVEs(same product + same CWE)
Same product
10 shownDebian:12:nats-server
Frequently asked(5)
What is CVE-2026-58208?
When was the CVE record for CVE-2026-58208 published?
Is CVE-2026-58208 actively exploited?
What is the CVSS score of CVE-2026-58208?
How do I remediate CVE-2026-58208?
Dependency Blast Radius
See which npm, PyPI, Go, and Maven packages are affected by CVE-2026-58208
Is Your Infrastructure Affected by CVE-2026-58208?
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