CVE-2021-3127

Name: CVE-2021-3127
Creator: NVD / NIST
Published: 2021-03-16T20:15:13.3+00:00
License: https://creativecommons.org/publicdomain/zero/1.0/

HIGHCVSS 7.5/10EPSS 1.46%

Last modified Jun 17, 2026

CVE-2021-3127 is a high-severity vulnerability rated 7.5/10 on the CVSS scale. NATS Server 2.x before 2.2.0 and JWT library before 2.0.1 have Incorrect Access Control because Import Token bindings are mishandled.. EPSS estimates a 1.46% chance of exploitation in the next 30 days.

Description

NATS Server 2.x before 2.2.0 and JWT library before 2.0.1 have Incorrect Access Control because Import Token bindings are mishandled.

Metrics

CVSS 3.1

7.5/10

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N

EPSS Probability

1.46%

70.3th percentile

Probability of exploitation in the next 30 days. Learn more

Weakness Enumeration

CWE-755

Affected Software

Vendor	Product	Versions
Linuxfoundation	Nats-Server	>= 2.0.0, < 2.2.0
Nats	Jwt Library	< 2.0.1

References

https://advisories.nats.io/CVE/CVE-2021-3127.txtExploit, Vendor Advisory
https://advisories.nats.io/CVE/CVE-2021-3127.txtExploit, Vendor Advisory

Timeline

Published: Mar 16, 2021
Last Modified: Jun 17, 2026
Status: Modified

Frequently Asked Questions

What is CVE-2021-3127?

NATS Server 2.x before 2.2.0 and JWT library before 2.0.1 have Incorrect Access Control because Import Token bindings are mishandled.

How severe is CVE-2021-3127?

CVE-2021-3127 has a CVSS score of 7.5/10 (HIGH severity). The EPSS model estimates a 1.46% probability of exploitation in the next 30 days.

How do I fix CVE-2021-3127?

Check the vendor references and advisories linked above for patched versions and mitigation guidance. You can also run a Strix scan to test if your systems are affected.

Are you affected by CVE-2021-3127?

Run a free Strix scan to check your systems for this vulnerability.

Scan your code now

Source: NVD / NIST