CVE-2021-28501

Public Exploit
An issue has recently been discovered in Arista EOS where the incorrect use of EOS's AAA API’s by the OpenConfig and TerminAttr agents could result in unrestricted access to the device for local users with nopassword configuration.

Description

An issue has recently been discovered in Arista EOS where the incorrect use of EOS's AAA API’s by the OpenConfig and TerminAttr agents could result in unrestricted access to the device for local users with nopassword configuration.

Remediation

Solution:

  • The recommended resolution is to upgrade to a remediated software version at your earliest convenience. Arista recommends customers move to the latest version of each release. To specifically address CVE-2021-28501 upgrade to TerminAttr v1.16.2 and later releases

Workaround:

  • On the affected versions, all vulnerabilities can be mitigated by disabling OpenConfig gNMI/gNOI and OpenConfig RESTCONF and TerminAttr. If use of these agents is required, a hotfix employing a proxy service can be deployed.
  • To mitigate CVE-2021-28501 with the continued use of the affected agents, a hotfix employing a proxy service can be deployed. The proxy is configured behind the gNMI/gNOI or RESTCONF server. The hotfix can be downloaded at https://www.arista.com/en/support/advisories-notices/sa-download/?sa=71-SecurityAdvisory0071Hotfix.i386.swix for 32 bit systems and https://www.arista.com/en/support/advisories-notices/sa-download/?sa=71-SecurityAdvisory0071Hotfix.x86_64.swix for 64 bit systems.

Category

9.1
CVSS
Severity: Critical
CVSS 3.1 •
CVSS 2.0 •
EPSS 0.29%
Vendor Advisory arista.com
Affected: Arista Networks Terminattr
Published at:
Updated at:

References

Link Tags
https://www.arista.com/en/support/advisories-notices/security-advisories/13449-security-advisory-0071 patch exploit vendor advisory mitigation

Frequently Asked Questions

What is the severity of CVE-2021-28501?
CVE-2021-28501 has been scored as a critical severity vulnerability.
How to fix CVE-2021-28501?
To fix CVE-2021-28501: The recommended resolution is to upgrade to a remediated software version at your earliest convenience. Arista recommends customers move to the latest version of each release. To specifically address CVE-2021-28501 upgrade to TerminAttr v1.16.2 and later releases
Is CVE-2021-28501 being actively exploited in the wild?
It is possible that CVE-2021-28501 is being exploited or will be exploited in a near future based on public information. According to its EPSS score, there is a ~0% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
What software or system is affected by CVE-2021-28501?
CVE-2021-28501 affects Arista Networks Terminattr.
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