Medium severity · published Jul 8, 2026
CVE-2026-58252
NATS Server: Subscribe Authz Bypass via Wildcard-Overlap
6.5
CVSS
0.5%
EPSS
No
On KEV
Description
NATS Server is a high-performance server for NATS.io, the cloud and edge native messaging system. Prior to 2.14.0, 2.12.7, and 2.11.16, an authenticated user could receive messages on denied subjects when a wildcard subscription overlapped with a configured wildcard deny rule but was not a subset of it, and queue subscriptions could also affect delivery to legitimate queue consumers. This issue is fixed in versions 2.14.0, 2.12.7, and 2.11.16.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N
Attack vector
Network
Complexity
Low
Privileges
Low
User interaction
None
Confidentiality
High
Integrity
None
Availability
None
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.5% · higher than 40% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
NA
nats-server · nats-io
< 2.11.16; >= 2.12.0-preview.1, < 2.12.7 · source: vendor, NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-58252
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-58252
Patch
https://github.com/nats-io/nats-server/commit/8ced85a11497f86704a95d960281480ce037386b
Patch
https://github.com/nats-io/nats-server/commit/a42a6d1e258eb5c3a2190384d31965a4b715e854
Patch
https://github.com/nats-io/nats-server/commit/e611ca9604697b02d8f22beb76037400a9cf72e6
Release Notes
https://github.com/nats-io/nats-server/releases/tag/v2.11.16
Release Notes
https://github.com/nats-io/nats-server/releases/tag/v2.12.7
Release Notes
https://github.com/nats-io/nats-server/releases/tag/v2.14.0
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