CVE-2026-33223
NATS Server: Incomplete Stripping of Nats-Request-Info Header Allows Identity Spoofing
CVSS Score
6.4
EPSS Score
0.0%
EPSS Percentile
7th
NATS-Server is a High-Performance server for NATS.io, a cloud and edge native messaging system. Prior to versions 2.11.15 and 2.12.6, the NATS message header `Nats-Request-Info:` is supposed to be a guarantee of identity by the NATS server, but the stripping of this header from inbound messages was not fully effective. An attacker with valid credentials for any regular client interface could thus spoof their identity to services which rely upon this header. Versions 2.11.15 and 2.12.6 contain a fix. No known workarounds are available.
| CWE | CWE-290 |
| Vendor | nats-io |
| Product | nats-server |
| Published | Mar 25, 2026 |
| Last Updated | Mar 26, 2026 |
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CVSS v3 Breakdown
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:L/I:L/A:N Attack Vector
Network
Attack Complexity
Low
Privileges Required
Low
User Interaction
None
Scope
Changed
Confidentiality
Low
Integrity
Low
Availability
None
Affected Versions
nats-io / nats-server
< 2.11.15 >= 2.12.0-RC.1, < 2.12.6