CVE-2026-33215 (GCVE-0-2026-33215)

Vulnerability from cvelistv5 – Published: 2026-03-24 20:55 – Updated: 2026-03-25 13:05
VLAI?
Title
NATS is vulnerable to MQTT hijacking via Client ID
Summary
NATS-Server is a High-Performance server for NATS.io, a cloud and edge native messaging system. The nats-server provides an MQTT client interface. Prior to versions 2.11.15 and 2.12.5, Sessions and Messages can by hijacked via MQTT Client ID malfeasance. Versions 2.11.15 and 2.12.5 patch the issue. No known workarounds are available.
Severity ?
6.5 (Medium)
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:L
CWE
  • CWE-287 - Improper Authentication
  • CWE-488 - Exposure of Data Element to Wrong Session
Assigner
References
Impacted products
Vendor Product Version
nats-io nats-server Affected: < 2.11.15
Affected: >= 2.12.0-RC.1, < 2.12.6
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Sightings

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Nomenclature

  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
  • Confirmed: The vulnerability has been validated from an analyst's perspective.
  • Published Proof of Concept: A public proof of concept is available for this vulnerability.
  • Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
  • Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
  • Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
  • Not confirmed: The user expressed doubt about the validity of the vulnerability.
  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.



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