No exploitation reportedFix available

CVE-2020-28466

Q: Is CVE-2020-28466 actively exploited?

Active exploitation of CVE-2020-28466 has not been confirmed. Its EPSS score was 3.7% on 2026-10-23, the estimated probability of exploitation in the next 30 days.

Q: What is the CVSS score for CVE-2020-28466?

CVE-2020-28466 has a CVSS v3 base score of 7.5 (HIGH severity), with vector string CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H.

No exploitation reported by the sources we read.

Published2021-03-07
Fixed in2.2.0

Am I affected?

With a domain, we read the version its public headers and pages expose. A distribution build can carry the fix under an older number.

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.

Timeline

dates in UTC

2021-03-0710:15CVE publishedNVD

Observed activity

isMalicious corpus · updated 2026-10-23 21:37 UTC

Indicators tagged with this CVE, per day0 indicators over 7 days

Block these indicators

Firewall list (EDL, text): https://api.ismalicious.com/edl/cve/CVE-2020-28466?format=txt
CSV export: https://api.ismalicious.com/edl/cve/CVE-2020-28466?format=csv
TAXII collection of exploited CVEs
The EDL and CSV take an API key on the Pro plan.

Versions per branch

NVD · OSV

Linuxfoundation nats-server

Branch	Affected	Fixed in	Source
2.x	≥ 2.0.0, < 2.2.0	2.2.0	NVD · OSV
2.2	< 2.2.0	2.2.0	OSV

as publishedRanges as NVD and OSV publish them; a distribution’s build can be fixed under an older number.

Fix

Update Linuxfoundation nats-server to 2.2.0

Advisories and patches

github.comPatch

Detection

Nuclei template: none so far
Exploit-DB: no entry
Proof-of-concept repositories: none listed

Sources

CNACVSS 3.17.5read 2026-10-23
NVDCVSS 3.17.5read 2026-10-23
NVDCVSS 2.05read 2026-10-23
FIRST EPSSEPSS score3.7 %2026-10-23
OSVaffected packages—

Technical details

CVSS v3 Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Published: 2021-03-07
Last Modified: 2026-06-17
NVD status: Modified

Frequently asked questions

What is CVE-2020-28466?

Is CVE-2020-28466 actively exploited?

Active exploitation of CVE-2020-28466 has not been confirmed. Its EPSS score was 3.7% on 2026-10-23, the estimated probability of exploitation in the next 30 days.

What is the CVSS score for CVE-2020-28466?

CVE-2020-28466 has a CVSS v3 base score of 7.5 (HIGH severity), with vector string CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H.

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