What’s Vulnerable › Vulnerabilities

CVE-2020-28466: Denial of Service (DoS)

• Severity: high (CVSS 7.5 v3.1)
• Exploited in the wild: not listed in CISA KEV
• EPSS: 3.7% probability of exploitation in the next 30 days
• Public exploit or detection template: none known
• Published: 2021-03-07 · updated 2026-06-17

Description

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.

Affected products

• nats-io nats-server: from 2.0.0 before 2.2.0 — fixed in 2.2.0

How to fix

Upgrade to a fixed version: nats-io nats-server 2.2.0. Check the vendor advisory for mitigations.

References

• http://www.openwall.com/lists/oss-security/2021/03/16/1
• http://www.openwall.com/lists/oss-security/2021/03/16/2
• https://github.com/nats-io/nats-server/pull/1731
• https://snyk.io/vuln/SNYK-GOLANG-GITHUBCOMNATSIONATSSERVERSERVER-1042967
• http://www.openwall.com/lists/oss-security/2021/03/16/1
• http://www.openwall.com/lists/oss-security/2021/03/16/2
• https://github.com/nats-io/nats-server/pull/1731
• https://snyk.io/vuln/SNYK-GOLANG-GITHUBCOMNATSIONATSSERVERSERVER-1042967

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