CVE-2022-20821
Cisco IOS XR Software Health Check Open Port Vulnerability
Cisco IOS XR Open Port Vulnerability is confirmed as actively exploited and is listed in the CISA KEV catalog.
Required action
Apply updates per vendor instructions.
CISA notes
https://nvd.nist.gov/vuln/detail/CVE-2022-20821
Description
A vulnerability in the health check RPM of Cisco IOS XR Software could allow an unauthenticated, remote attacker to access the Redis instance that is running within the NOSi container. This vulnerability exists because the health check RPM opens TCP port 6379 by default upon activation. An attacker could exploit this vulnerability by connecting to the Redis instance on the open port. A successful exploit could allow the attacker to write to the Redis in-memory database, write arbitrary files to the container filesystem, and retrieve information about the Redis database. Given the configuration of the sandboxed container that the Redis instance runs in, a remote attacker would be unable to execute remote code or abuse the integrity of the Cisco IOS XR Software host system.
Severity
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:NExploitation Context
as of October 15, 2026- CISA added CVE-2022-20821 to the KEV catalog 3 days before its CVE record was published.
- It is one of 101 Cisco entries in the CISA KEV catalog, and one of 50 added in 2022.
- Its current EPSS score (11.5%) is higher than that of 28% of CISA KEV entries.
Affected Products
| Vendor | Product | Affected versions |
|---|---|---|
| Cisco | Cisco Cisco IOS XR Software | n/a |
References
1 LinksRecord Details
More from Cisco
Cisco IOS XR Software Cisco Discovery Protocol Format String Vulnerability
Cisco IOS XR Border Gateway Protocol (BGP) Denial-of-Service Vulnerability
Cisco IOS XR Software DVMRP Memory Exhaustion Vulnerability
Cisco IOS XR Software DVMRP Memory Exhaustion Vulnerabilities
Related
Tool categories
CVE record data © The MITRE Corporation, used under the CVE Terms of Use. Exploited-in-the-wild data from the CISA Known Exploited Vulnerabilities catalog (CC0). Exploit prediction scores by FIRST EPSS (first.org/epss). This site is not endorsed or certified by MITRE, NVD, CISA, or FIRST.