# CVE-2022-20821: Cisco IOS XR Software Health Check Open Port Vulnerability

> CVE-2022-20821: Cisco IOS XR Software Health Check Open Port Vulnerability. CVSS 6.5 (CVSS 3.1), in CISA KEV.

Canonical: https://rewindex.com/cve/CVE-2022-20821
Last updated: 2025-10-21T23:15:39Z

- Published: 2022-05-26 14:00 UTC · Updated: 2025-10-21 23:15 UTC · Assigner: cisco
- CVSS: 6.5 (CVSS 3.1) · Severity: Medium · Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N
- EPSS: 11.5%, 96th percentile (scored 2026-10-25)
- CISA KEV: yes, added 2022-05-23, federal due date 2022-06-13, ransomware use: Unknown
- CWE: CWE-200

## 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.

## CISA required action

Apply updates per vendor instructions.

## Affected vendors and products

- Cisco: Cisco IOS XR Software

## References

- [CVE record on cve.org](https://www.cve.org/CVERecord?id=CVE-2022-20821)
- [NVD entry](https://nvd.nist.gov/vuln/detail/CVE-2022-20821)
- [https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-iosxr-redis-ABJyE5xK](https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-iosxr-redis-ABJyE5xK)

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_Sources: CVE records from the CVE Program (cve.org). CVE® is a registered trademark of The MITRE Corporation. (https://www.cve.org/) This product uses data from the NVD API but is not endorsed or certified by the NVD. (https://nvd.nist.gov/) Known Exploited Vulnerabilities catalog from CISA. (https://www.cisa.gov/known-exploited-vulnerabilities-catalog) EPSS scores from FIRST (Exploit Prediction Scoring System). (https://www.first.org/epss/)_


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Canonical: https://rewindex.com/cve/CVE-2022-20821 · Markdown: https://rewindex.com/cve/CVE-2022-20821.md · JSON: https://rewindex.com/api/v1/cves/CVE-2022-20821 · Data licensed CC BY 4.0 (https://creativecommons.org/licenses/by/4.0/) · Generated 2026-10-26T03:12:54.829Z