CVE-2026-33216
NATS Server MQTT monitoring endpoints leak passwords via misclassified JWT.
Is CVE-2026-33216 being exploited?
Not confirmed. CVE-2026-33216 does not appear in CISA's Known Exploited Vulnerabilities catalog, which records only exploitation that has been observed and reported publicly. That is evidence of absence of a report, not evidence the flaw is unattacked. EPSS currently estimates a 0.36% probability of exploitation in the next 30 days.
How severe is CVE-2026-33216?
CVE-2026-33216 is rated High with a CVSS score of 8.6. Severity describes how bad exploitation would be, not how likely it is: pair it with exploitation evidence before deciding what to patch first.
Is there a patch for CVE-2026-33216?
Yes. A fix has been recorded for CVE-2026-33216. The vendor advisory is the authority on the exact fixed version — apply it from there rather than from a summary.
What does CVE-2026-33216 affect?
CVE-2026-33216 affects NATS Server (MQTT deployments). Confirm the exact affected versions against the vendor advisory before deciding you are exposed.
What should I do about CVE-2026-33216?
Upgrade to 2.11.15 or 2.12.6; secure monitoring endpoints.
Exploitation status reflects CISA's KEV catalog as we last synced it. Check the catalog directly.
Credential exposure via monitoring endpoint; attackers could access MQTT passwords and compromise brokers.
Patch when possible
- affected< 2.11.15
- affected>= 2.12.0-RC.1 and < 2.12.6
As published in the CVE Program record. A version outside these ranges is not a statement that it is unaffected — vendors sometimes understate a range, and distribution-backported builds carry upstream numbers that do not reflect what was patched into them.