Improper Authorization in nats-server - CVE-2026-58252
Published: June 30, 2026
Vulnerability identifier: #VU135925
CSH Severity: Low
CVSS v4: 7.1 [CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N]
CVE-ID: CVE-2026-58252
CWE-ID: CWE-285
Exploitation vector: Remote access
Exploit availability:
No public exploit available
Vulnerability details
The vulnerability allows a remote user to disclose sensitive information.
The vulnerability exists due to improper authorization in the subscription permission system when processing wildcard subscription requests that overlap with wildcard deny rules. A remote user can create a wildcard subscription to receive messages on denied subjects to disclose sensitive information.
The issue requires valid credentials and a permission configuration with overlapping wildcard allow and deny patterns. Queue subscriptions may also affect delivery to legitimate queue consumers.
Affected software
nats-server
How to mitigate CVE-2026-58252
Install security update from vendor's website.
nats-server - addressed in versions 2.11.16, 2.12.7, 2.14.0