Arcadyan Buffalo Firmware
YES - ON THE CISA KEV LIST
CVE-2021-20090
Arcadyan Buffalo Firmware Path Traversal Vulnerability
overdue since 2021-11-17
Arcadyan: 1 entries (0.1% of all KEV entries are from this vendor); 0 added in 2026.
BOD 26-04 note: this is the date printed in the CISA catalog. A federal agency's actual deadline is set by its SSVC tier - Act (3 days), Attend (14 days), Track (60 days), or the next scheduled upgrade - counted from the KEV listing date or the date the vulnerability is identified in its environment, whichever comes first. Use the tier helper on each CVE page for your own window.
Your BOD 26-04 window (SSVC tier helper)
Your remediation window ends:
Description
Arcadyan Buffalo firmware contains a path traversal vulnerability that could allow unauthenticated, remote attackers to bypass authentication and access sensitive information. This vulnerability affects multiple routers across several different vendors.
Required action (CISA)
Apply updates per vendor instructions.
Notes
https://nvd.nist.gov/vuln/detail/CVE-2021-20090
References
Other KEV entries for this vendor: Arcadyan
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