CVE-2022-20821
Cisco IOS XR Open Port Vulnerability
Published May 23, 2022 · updated Jun 16, 2026 · cisco ios xr
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
Detection, updates, and resolution for this record.
May 23, 2022 · Catalog
Detected
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
May 23, 2022 · CISA KEV
Known exploited
Apply updates per vendor instructions.
Jun 13, 2022 · CISA KEV
Remediation due
Apply updates per vendor instructions.
Jun 16, 2026 · Catalog
Updated
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
Required action
Apply updates per vendor instructions.
CISA due date Jun 13, 2022
Affected
- cpe cisco/ios xrversion unspecified
- vendor Cisco IOS XRversion unspecified
Sources
- CISA KEVCVE-2022-20821
Cisco IOS XR software health check opens TCP port 6379 by default on activation. An attacker can connect to the Redis instance on the open port and allow access to the Redis instance that is running within the NOSi container.
cisa.gov - CVE.orgCVE-2022-20821
Official CVE identifier
cve.org - FIRST EPSSCVE-2022-20821
30-day exploitation probability 11.5%
first.org - NIST NVDCVE-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 acti
nvd.nist.gov