Medium severity · published May 26, 2022
CVE-2022-20821
Cisco IOS XR Software Health Check Open Port Vulnerability
In wildKEV
6.5
CVSS
11.5%
EPSS
Yes
On KEV
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.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
None
Confidentiality
Low
Integrity
Low
Availability
None
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)11.5% · higher than 96% of CVEs
Exploited in the wildYes
CISA KEVListed May 23, 2022
Federal remediation dueJun 13, 2022
Ransomware campaign useNot known
Affected products
Which versions
CI
Cisco IOS XR Software · Cisco
All versions, or not specified · source: vendor
IX
Ios XR · Cisco
All versions, or not specified · source: NVD, KEV
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2022-20821
CVE.org
https://www.cve.org/CVERecord?id=CVE-2022-20821
CISA KEV catalogue
https://www.cisa.gov/known-exploited-vulnerabilities-catalog
vendor-advisory
https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-iosxr-redis-ABJyE5xK
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