CVE-2021-28506

Public Exploit
An issue has recently been discovered in Arista EOS where certain gNOI APIs incorrectly skip authorization and authentication which could potentially allow a factory reset of the device.

Description

An issue has recently been discovered in Arista EOS where certain gNOI APIs incorrectly skip authorization and authentication which could potentially allow a factory reset of the device.

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. CVE-2021-28506 has been fixed in the following releases: 4.26.3M and later releases in the 4.26.x train 4.25.6M and later releases in the 4.25.x train 4.25.4.1M and later releases in the 4.25.4.x train 4.24.8M and later releases in the 4.24.x train

Workaround:

  • No mitigation options available
  • To mitigate CVE-2021-28506 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.

Categories

9.1
CVSS
Severity: Critical
CVSS 3.1 •
CVSS 2.0 •
EPSS 0.48%
Vendor Advisory arista.com
Affected: Arista Networks EOS
Published at:
Updated at:

References

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

Frequently Asked Questions

What is the severity of CVE-2021-28506?
CVE-2021-28506 has been scored as a critical severity vulnerability.
How to fix CVE-2021-28506?
To fix CVE-2021-28506: 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. CVE-2021-28506 has been fixed in the following releases: 4.26.3M and later releases in the 4.26.x train 4.25.6M and later releases in the 4.25.x train 4.25.4.1M and later releases in the 4.25.4.x train 4.24.8M and later releases in the 4.24.x train
Is CVE-2021-28506 being actively exploited in the wild?
It is possible that CVE-2021-28506 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-2021-28506?
CVE-2021-28506 affects Arista Networks EOS.
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