CVE-2026-33247: Github.com/nats io/nats server/v2 NATS Credentials Are Exposed Vulnerability
HIGHCVE-2026-33247 is a HIGH (CVSS 7.4) nats credentials are exposed vulnerability (CWE-215: Insertion of Sensitive Information Into Debugging Code) affecting Github.com/nats io/nats server/v2 libraries in the Go ecosystem. The issue involves nats credentials are exposed in monitoring port via command-line argv. Remediation is available by upgrading affected packages to version 2.11.15, 2.12.6.
CVE-2026-33247 at a Glance
Security Impact
CVSS: 7.4
The security impact metrics below are parsed directly from the CVSS v3.1 vector string (CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N).
How to Fix CVE-2026-33247
To remediate this vulnerability, upgrade all affected Github.com/nats io/nats server/v2 dependencies to a patched release. Both direct and transitive dependencies should be checked, as frameworks or security libraries may pull in vulnerable versions transitively.
Upgrade github.com/nats-io/nats-server/v2 to 2.11.15Upgrade github.com/nats-io/nats-server/v2 to 2.12.6Run the following command in your project directory to verify that all resolved dependencies use the patched release:
inspect dependencies for github.com/nats-io/nats-server/v2How to Check if You Are Affected
To determine whether your application is affected by CVE-2026-33247, inspect your project dependencies for Github.com/nats io/nats server/v2:
inspect dependencies for github.com/nats-io/nats-server/v2Analyze the terminal output to locate any version of Github.com/nats io/nats server/v2 in your dependency tree. If any resolved version matches the vulnerable ranges listed in the table below (for example, versions earlier than 2.11.15), your application is affected.
Note: Verify declared build manifests and deployed runtime container environments.
Technical Details
Vulnerability Mechanism & Technical Analysis
This vulnerability is classified under CWE-215: Insertion of Sensitive Information Into Debugging Code, where the product inserts sensitive information into debugging code, which could expose this information if the debugging code is not disabled in production. In Github.com/nats io/nats server/v2, software state validation or input boundaries are circumvented during processing. Review the official source advisory statement below for specific affected components, classes, and reproduction details.
Source Advisory Statement
CVE-2026-33247 Affected Github.com/nats io/nats server/v2 Versions
2 component(s)| Product / Package | Ecosystem | Affected Versions | Fixed Version |
|---|---|---|---|
|
github.com/nats-io/nats-server/v2
|
Go |
< 2.11.15
|
2.11.15
|
|
github.com/nats-io/nats-server/v2
|
Go |
≥ 2.12.0-RC.1
< 2.12.6
|
2.12.6
|
References
Frequently Asked Questions
What is CVE-2026-33247?
Which Github.com/nats io/nats server/v2 versions are affected?
What version fixes CVE-2026-33247?
Is github.com/nats-io/nats-server/v2 affected?
What is the CVSS score of CVE-2026-33247?
What CWE is associated with CVE-2026-33247?
How can I check Go dependencies for CVE-2026-33247?
Machine-readable OSV JSON
OSV v1.5 Schema
{
"schema_version" : "1.4.0",
"id" : "GHSA-x6g4-f6q3-fqvv",
"modified" : "2026-03-27T20:57:01Z",
"published" : "2026-03-24T20:44:00Z",
"aliases" : [ "CVE-2026-33247" ],
"summary" : "NATS credentials are exposed in monitoring port via command-line argv",
"details" : "### Background\n\nNATS.io is a high performance open source pub-sub distributed communication technology, built for the cloud, on-premise, IoT, and edge computing.\n\nThe nats-server provides an optional monitoring port, which provides access to sensitive data. The nats-server can take certain configuration options on the command-line instead of requiring a configuration file.\n\n\n### Problem Description\n\nIf a nats-server is run with static credentials for all clients provided via argv (the command-line), then those credentials are visible to any user who can see the monitoring port, if that too is enabled.\n\nThe `/debug/vars` end-point contains an unredacted copy of argv.\n\n### Patches\n\nFixed in nats-server 2.12.6 & 2.11.15\n\n### Workarounds\n\nThe NATS Maintainers are bemused at the concept of someone deploying a real configuration using `--pass` to avoid a config file, but also enabling monitoring.\n\nConfigure credentials inside a configuration file instead of via argv.\n\nDo not enable the monitoring port if using secrets in argv.\n\nBest practice remains to not expose the monitoring port to the Internet, or to untrusted network sources.",
"severity" : [ {
"type" : "CVSS_V3",
"score" : "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N"
} ],
"affected" : [ {
"package" : {
"ecosystem" : "Go",
"name" : "github.com/nats-io/nats-server/v2"
},
"ranges" : [ {
"type" : "ECOSYSTEM",
"events" : [ {
"introduced" : "0"
}, {
"fixed" : "2.11.15"
} ]
} ]
}, {
"package" : {
"ecosystem" : "Go",
"name" : "github.com/nats-io/nats-server/v2"
},
"ranges" : [ {
"type" : "ECOSYSTEM",
"events" : [ {
"introduced" : "2.12.0-RC.1"
}, {
"fixed" : "2.12.6"
} ]
} ]
} ],
"references" : [ {
"type" : "WEB",
"url" : "https://github.com/nats-io/nats-server/security/advisories/GHSA-x6g4-f6q3-fqvv"
}, {
"type" : "ADVISORY",
"url" : "https://nvd.nist.gov/vuln/detail/CVE-2026-33247"
}, {
"type" : "WEB",
"url" : "https://advisories.nats.io/CVE/secnote-2026-14.txt"
}, {
"type" : "PACKAGE",
"url" : "https://github.com/nats-io/nats-server"
}, {
"type" : "WEB",
"url" : "https://pkg.go.dev/vuln/GO-2026-4827"
} ],
"database_specific" : {
"cwe_ids" : [ "CWE-215" ],
"severity" : "HIGH",
"github_reviewed" : true,
"github_reviewed_at" : "2026-03-24T20:44:00Z",
"nvd_published_at" : "2026-03-25T20:16:33Z"
}
}