CVE-2023-46129: linuxfoundation nats-server Use of Hard-coded Cryptographic Key

Vulnerability summary

CVE-2023-46129 is a high (CVSS 7.5) Use of Hard-coded Cryptographic Key vulnerability in linuxfoundation nats-server. EPSS estimates a 0.37% chance of exploitation in the next 30 days, higher than 29.5% of scored vulnerabilities.

Timeline

1. 30-10-2023
   PublishedVulnerability first disclosed.
2. 27-02-2025
   Last modifiedVulnerability information updated.

Description

NATS.io is a high performance open source pub-sub distributed communication technology, built for the cloud, on-premise, IoT, and edge computing. The cryptographic key handling library, nkeys, recently gained support for encryption, not just for signing/authentication. This is used in nats-server 2.10 (Sep 2023) and newer for authentication callouts. In nkeys versions 0.4.0 through 0.4.5, corresponding with NATS server versions 2.10.0 through 2.10.3, the nkeys library's `xkeys` encryption handling logic mistakenly passed an array by value into an internal function, where the function mutated that buffer to populate the encryption key to use. As a result, all encryption was actually to an all-zeros key. This affects encryption only, not signing. FIXME: FILL IN IMPACT ON NATS-SERVER AUTH CALLOUT SECURITY. nkeys Go library 0.4.6, corresponding with NATS Server 2.10.4, has a patch for this issue. No known workarounds are available. For any application handling auth callouts in Go, if using the nkeys library, update the dependency, recompile and deploy that in lockstep.

• CWE-321Use of Hard-coded Cryptographic KeyThe product uses a hard-coded, unchangeable cryptographic key.
• CWE-325Missing Cryptographic StepThe product does not implement a required step in a cryptographic algorithm, resulting in weaker encryption than advertised by the algorithm.