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TI-2026-25667 Aliases CVE-2026-33249GHSA-8m2x-3m6q-6w8j

NATS: Message tracing can be redirected to arbitrary subject

Priority LOW 20CWE-863Published · Updated

Key facts

Attack vector
Network
Privileges required
Low
User interaction
None
Attack complexity
Low
Impact type
Security bypass
Confidentiality · integrity · availability
None · Low · None
Fix status
Partial Red Hat: 2 without a fix

Attack profile from CVSS 3.1 · CNA. Fix status from CNA, GitHub and Red Hat. Impact type from CWE-863.

Summary

NATS-Server is a High-Performance server for NATS.io, a cloud and edge native messaging system. Starting in version 2.11.0 and prior to versions 2.11.15 and 2.12.6, a valid client which uses message tracing headers can indicate that the trace messages can be sent to an arbitrary valid subject, including those to which the client does not have publish permission. The payload is a valid trace message and not chosen by the attacker. Versions 2.11.15 and 2.12.6 contain a fix. No known workarounds are available.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00237 14th percentileScored 2026-11-07
Fix Partial nats-server (nats-io): 2.11.15, 2.12.6github.com/nats-io/nats-server/v2 (Go): 2.11.15, 2.12.6Red Hat: 2 without a fix

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
None
Automatable
No
Technical impact
Partial

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

VendorProductAffected versionsFixed inStatusSource
backstagenats-server2.11.0 to before 2.11.15; 2.12.0-preview.1 to before 2.12.62.11.15, 2.12.6Patch availableCNA
—github.com/nats-io/nats-server/v2 (Go)2.11.0 to before 2.11.152.11.15Patch availableGHSA-8m2x-3m6q-6w8j
—github.com/nats-io/nats-server/v2 (Go)2.12.0-preview.1 to before 2.12.62.12.6Patch availableGHSA-8m2x-3m6q-6w8j
  • nats-server Vendorbackstage Affected 2.11.0 to before 2.11.15; 2.12.0-preview.1 to before 2.12.6 Fixed in 2.11.15, 2.12.6 Patch available CNA
  • github.com/nats-io/nats-server/v2 (Go) Vendor— Affected 2.11.0 to before 2.11.15 Fixed in 2.11.15 Patch available GHSA-8m2x-3m6q-6w8j
  • github.com/nats-io/nats-server/v2 (Go) Vendor— Affected 2.12.0-preview.1 to before 2.12.6 Fixed in 2.12.6 Patch available GHSA-8m2x-3m6q-6w8j

CPE configurations NVD · 1

CPEVersionsRoleVendor
cpe:2.3:a:linuxfoundation:nats-server:*:*:*:*:*:*:*:*2.11.0 to before 2.11.15; 2.12.0 to before 2.12.6Vulnerablebackstage
  • cpe:2.3:a:linuxfoundation:nats-server:*:*:*:*:*:*:*:* Versions 2.11.0 to before 2.11.15; 2.12.0 to before 2.12.6 Vulnerable ·backstage

Remediation

  • Fix · CNA nats-server (nats-io) Fixed in 2.11.15, 2.12.6
  • Fix · GHSA-8m2x-3m6q-6w8j github.com/nats-io/nats-server/v2 (Go) Fixed in 2.11.15 Advisory →
  • Fix · GHSA-8m2x-3m6q-6w8j github.com/nats-io/nats-server/v2 (Go) Fixed in 2.12.6 Advisory →

Vendor assessments

Red Hat

Red Hat rating: Moderate. Red Hat's page for this CVE →

ProductStatusPlan or fix
Multicluster Global HubAffectedNo fix yet: Fix deferred
Red Hat OpenShift Container Platform 4AffectedNo fix yet: Fix deferred

Timeline

  1. 2026-10-02 Threatist record created from CVE-2026-33249
  2. 2026-10-03 Alias added: GHSA-8m2x-3m6q-6w8j

References

Advisory 3

Other 1

  • TI-2026-22233 NATS: Pre-auth remote server crash via WebSocket frame length overflow in wsRead CVSS 3.1HIGH 7.5
  • TI-2022-11116 NATS nats-server 2.2.0 through 2.7.4 allows directory traversal because of an unintended… CVSS 3.1CRITICAL 9.8
  • TI-2020-16319 The JWT library in NATS nats-server before 2.1.9 has Incorrect Access Control because of… CVSS 3.1CRITICAL 9.8
  • TI-2026-25637 NATS has MQTT plaintext password disclosure CVSS 3.1HIGH 8.6
  • TI-2022-08320 NATS nats-server before 2.7.2 has Incorrect Access Control. CVSS 3.1HIGH 8.8
  • TI-2026-41950 NATS Server: Pre-auth server crash via double INFO in leafnode handshake CVSS 3.1HIGH 7.5
See all 35 →

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences