Open-Source Security Intelligence

Know every vulnerability
before it knows you.

DevGuard continuously monitors your dependencies and alerts you when CVEs like this one affect your stack — with real-time threat intelligence built for developers.

Checkout DevGuardView on GitHub
Search

GHSA-jj54-5q2m-q7pj

Published May 14, 2024·Last modified Feb 4, 2026
Affected Components(0)

No affected components available

Description

(This advisory is canonically https://advisories.nats.io/CVE/CVE-2021-32026.txt)

Problem Description

The NATS server by default uses a restricted set of modern ciphersuites for TLS. This selection can be overridden through configuration. The defaults include just RSA and ECDSA with either AES/GCM with a SHA2 digest or ChaCha20/Poly1305.

The configuration system allows for extensive use of CLI options to override configuration settings. When using these to set a key/cert for TLS, the restricted ciphersuite settings were lost, enabling all ciphersuites supported by Go by default.

None of these additional ciphersuites are broken, so the NATS maintainers have fixed this in public git and the next release is not being hurried, nor is this security advisory embargoed.

Affected versions

NATS Server:

  • All versions prior to 2.2.3
  • fixed with nats-io/nats-server commit ffccc2e1bd (2021-04-29)

Impact

If a server administrator chooses to start the nats-server with TLS configuration parameters provided on the command-line, then clients can negotiate TLS ciphersuites which were not expected.

Workaround

Use a configuration file to set the TLS parameters instead of command-line options.

Solution

Upgrade the NATS server.

Credits

This issue was identified and reported by SimCorp.

Risk Scores
Base Score
0.0

Measures severity based on intrinsic characteristics of the vulnerability, independent of environment.

Threat Intelligence
0.0

No exploitation activity has been observed at this time. Continue routine monitoring.

EPSS
N/A

Probability that this vulnerability will be exploited in the wild within the next 30 days.

Exploit
Not available

We did not find any exploit available. Neither in GitHub repositories nor in the Exploit-Database.

Related Vulnerabilities
  • CVE-2021-32026
    Alias
Scan your project

Continuously monitor your dependencies and get alerted when vulnerabilities like this one affect your stack.

Checkout DevGuard