CVE-2020-28466: Github.com/nats io/nats server Denial of Service Vulnerability
HIGHCVE-2020-28466 is a HIGH (CVSS 7.5) denial of service vulnerability (CWE-400: Uncontrolled Resource Consumption) affecting Github.com/nats io/nats server libraries in the Go ecosystem. The issue involves denial of service in github.com/nats-io/nats-server/server. Remediation is available by upgrading affected packages to version 2.2.0.
CVE-2020-28466 at a Glance
Security Impact
CVSS: 7.5
The security impact metrics below are parsed directly from the CVSS v3.1 vector string (CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H).
How to Fix CVE-2020-28466
To remediate this vulnerability, upgrade all affected Github.com/nats io/nats server 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 to 2.2.0Upgrade github.com/nats-io/nats-server/v2 to 2.2.0Run 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-serverHow to Check if You Are Affected
To determine whether your application is affected by CVE-2020-28466, inspect your project dependencies for Github.com/nats io/nats server:
inspect dependencies for github.com/nats-io/nats-serverAnalyze the terminal output to locate any version of Github.com/nats io/nats server in your dependency tree. If any resolved version matches the vulnerable ranges listed in the table below (for example, versions earlier than 2.2.0), 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-400: Uncontrolled Resource Consumption, where the product does not properly control the allocation and maintenance of a limited resource. In Github.com/nats io/nats server, 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-2020-28466 Affected Github.com/nats io/nats server Versions
2 component(s)| Product / Package | Ecosystem | Affected Versions | Fixed Version |
|---|---|---|---|
|
github.com/nats-io/nats-server
|
Go |
< 2.2.0
|
2.2.0
|
|
github.com/nats-io/nats-server/v2
|
Go |
< 2.2.0
|
2.2.0
|
References
Frequently Asked Questions
What is CVE-2020-28466?
Which Github.com/nats io/nats server versions are affected?
What version fixes CVE-2020-28466?
Is github.com/nats-io/nats-server affected?
Is github.com/nats-io/nats-server/v2 affected?
What is the CVSS score of CVE-2020-28466?
What CWE is associated with CVE-2020-28466?
How can I check Go dependencies for CVE-2020-28466?
Machine-readable OSV JSON
OSV v1.5 Schema
{
"schema_version" : "1.4.0",
"id" : "GHSA-m4jx-6526-vvhm",
"modified" : "2026-03-30T20:36:42Z",
"published" : "2022-02-15T01:57:18Z",
"aliases" : [ "CVE-2020-28466" ],
"summary" : "Denial of service in github.com/nats-io/nats-server/server",
"details" : "This affects all versions of package github.com/nats-io/nats-server/server. Untrusted accounts are able to crash the server using configs that represent a service export/import cycles. Disclaimer from the maintainers - Running a NATS service which is exposed to untrusted users presents a heightened risk. Any remote execution flaw or equivalent seriousness, or denial-of-service by unauthenticated users, will lead to prompt releases by the NATS maintainers. Fixes for denial of service issues with no threat of remote execution, when limited to account holders, are likely to just be committed to the main development branch with no special attention. Those who are running such services are encouraged to build regularly from git.",
"severity" : [ {
"type" : "CVSS_V3",
"score" : "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H"
} ],
"affected" : [ {
"package" : {
"ecosystem" : "Go",
"name" : "github.com/nats-io/nats-server"
},
"ranges" : [ {
"type" : "ECOSYSTEM",
"events" : [ {
"introduced" : "0"
}, {
"fixed" : "2.2.0"
} ]
} ]
}, {
"package" : {
"ecosystem" : "Go",
"name" : "github.com/nats-io/nats-server/v2"
},
"ranges" : [ {
"type" : "ECOSYSTEM",
"events" : [ {
"introduced" : "0"
}, {
"fixed" : "2.2.0"
} ]
} ]
} ],
"references" : [ {
"type" : "ADVISORY",
"url" : "https://nvd.nist.gov/vuln/detail/CVE-2020-28466"
}, {
"type" : "WEB",
"url" : "https://github.com/nats-io/nats-server/pull/1731"
}, {
"type" : "WEB",
"url" : "https://github.com/nats-io/nats-server/pull/1731/commits/2e3c22672936f4980d343fb1d328b38919e74796"
}, {
"type" : "WEB",
"url" : "https://pkg.go.dev/vuln/GO-2022-0855"
}, {
"type" : "WEB",
"url" : "https://snyk.io/vuln/SNYK-GOLANG-GITHUBCOMNATSIONATSSERVERSERVER-1042967"
}, {
"type" : "WEB",
"url" : "http://www.openwall.com/lists/oss-security/2021/03/16/1"
}, {
"type" : "WEB",
"url" : "http://www.openwall.com/lists/oss-security/2021/03/16/2"
} ],
"database_specific" : {
"cwe_ids" : [ "CWE-400" ],
"severity" : "HIGH",
"github_reviewed" : true,
"github_reviewed_at" : "2021-05-12T20:38:22Z",
"nvd_published_at" : "2021-03-07T10:15:12Z"
}
}