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ExploitedIn CISA KEV

CVE-2022-20821

Exploitation confirmed. First attested on 2022-05-23 by CISA-ADP, CISA KEV, GCVE · kevintel.

  • Published2022-05-26
  • WeaknessCWE-200

Am I affected?

With a domain, we read the version its public headers and pages expose. A distribution build can carry the fix under an older number.

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.

Timeline

dates in UTC
  1. 2022-05-23Added to the CISA KEV catalogCISA KEV
  2. 2022-05-23Listed as exploited by GCVEGCVE
  3. 2022-05-23Exploitation first reportedCISA KEV
  4. 2022-05-2614:15CVE publishedNVD
  5. 2024-10-2916:11SSVC exploitation set to activeCISA-ADP

Observed activity

isMalicious corpus · updated 2026-11-03 21:37 UTC
Indicators tagged with this CVE, per day0 indicators over 7 days
Block these indicators
  • Firewall list (EDL, text): https://api.ismalicious.com/edl/cve/CVE-2022-20821?format=txt
  • CSV export: https://api.ismalicious.com/edl/cve/CVE-2022-20821?format=csv
  • TAXII collection of exploited CVEs
  • The EDL and CSV take an API key on the Pro plan.

Versions per branch

NVD
Cisco ios xrversion to verify
BranchAffectedFixed in
—all versionsno fix published

as publishedRanges as NVD and OSV publish them; a distribution’s build can be fixed under an older number.

Products declared by the CNA1 product

As cisco, the CNA that assigned this CVE, declared them in the CVE record; versions as written.

  • Cisco IOS XR Software

Source: the CNA record (CVE Program), © The MITRE Corporation,CVE Terms of UseCVE recordupdated 2022-05-26

Fix

  1. CISA’s required action: Apply updates per vendor instructions.due 2022-06-13

Advisories and patches

Detection

Nuclei template
none so far
ProjectDiscovery
Exploit-DB
no entry
Exploit-DB
Proof-of-concept repositories
none listed
PoC-in-GitHub
Metasploit modules
none listed
Metasploit Framework

CISA Known Exploited Vulnerability

Date Added
2022-05-23
Patch Due Date
2022-06-13
Ransomware Use
Unknown
Required Action
Apply updates per vendor instructions.

Sources

Identifiers

Technical details

CVSS v3 Vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N
Published
2022-05-26
Last Modified
2026-06-17
NVD status
Analyzed
GitHub Advisory
GHSA-6whc-cmc9-99q6

Frequently asked questions

What is CVE-2022-20821?

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.

Is CVE-2022-20821 actively exploited?

Yes. CVE-2022-20821 is on the CISA Known Exploited Vulnerabilities (KEV) catalog, meaning it has been confirmed as actively exploited in the wild. CISA requires federal agencies to patch by 2022-06-13.

What is the CVSS score for CVE-2022-20821?

CVE-2022-20821 has a CVSS v3 base score of 6.5 (MEDIUM severity), with vector string CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N.

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Sources for this record