Improper access control in nats-server - CVE-2020-26892
Published: June 29, 2022 / Updated: June 30, 2026
Vulnerability identifier: #VU64780
CSH Severity: High
CVSS v4: 9.3 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N]
CVE-ID: CVE-2020-26892
CWE-ID: CWE-284
Exploitation vector: Remote access
Exploit availability:
No public exploit available
Vulnerability details
The vulnerability allows a remote attacker to execute arbitrary code on the system.
The vulnerability exists due to improper access restrictions in JWT library in NATS nats-server when handling expired credentials. A remote attacker can send a specially crafted request, gain unauthorized access and execute arbitrary code on the system.
Affected software
nats-server
Cloud Pak for Security (CP4S)
Fedora
nats-server
Cloud Pak for Security (CP4S)
Fedora
nats-server
How to mitigate CVE-2020-26892
Install update from vendor's website.
nats-server - update to 2.1.9
Cloud Pak for Security (CP4S) - update to 1.10.7.0
nats-server - update to 2.1.9-1.fc33
Cloud Pak for Security (CP4S) - update to 1.10.7.0
nats-server - update to 2.1.9-1.fc33