CVE-2022-20821
mediumpriority · act · 90OT risk · criticalKEV · exploitedEPSS 0.115 · 96 %ileEURUUSadded 2022-05-23remediate by 2022-06-13
required action Apply updates per vendor instructions.
EPSS · scored 2026-10-27
Cisco IOS XR Open Port Vulnerability
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.
remediations
Vendor fix, mitigation, or workaround guidance, as published by each source.
A vendor fix is available.
- FixedCisco IOS XR Softwarecisco_csaf
Cisco has released software updates that address this vulnerability.
https://software.cisco.com
cvss
Technical severity, 0–10. One row per scoring source.
base score 0–10 · higher = more severe · hover a vector to decode
ssvc
A stakeholder decision — act, attend, or track — from exploitation and impact.
weaknesses
The CWE weakness classes this flaw belongs to.
ATT&CK techniques
ATT&CK techniques this enables or maps to.
affected products (4)
Products and version ranges known to be affected.
advisories (1)
Vendor and ecosystem advisories describing this.
- cisco-sa-iosxr-redis-ABJyE5xKCisco IOS XR Software Health Check Open Port Vulnerability2022-05-20csaf · cisco_csafUS
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. Cisco has released software updates that address this vulnerability. There are workarounds that address this vulnerability.
also known as (4)
Other names and identifiers for this entity.
sources
Which sources assert this record, and when.
references (8)
External citations — patches, advisories, analysis.
- https://cxsecurity.com/cveshow/CVE-2022-20821/cnnvd
- https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-iosxr-redis-ABJyE5xKcnnvd
- https://vigilance.fr/vulnerability/Cisco-IOS-XR-ingress-filtrering-bypass-for-Redis-38419cnnvd
- https://www.auscert.org.au/bulletins/ESB-2022.2507cnnvd
- https://www.cybersecurity-help.cz/vdb/SB2022052101cnnvd
- https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-iosxr-redis-ABJyE5xKenisa_euvd
- https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-iosxr-redis-ABJyE5xKVendor Advisorynvd
- https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2022-20821US Government Resourcenvd
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