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CVE-2021-20090: Arcadyan Buffalo Firmware Path Traversal Vulnerability
Arcadyan Buffalo Firmware · in CISA KEV since 2021-11-03
2021-11-03added to KEV
2021-11-17federal remediation due date
99.98%EPSS exploit probability (30 days) 100.0th percentile
9.8 CRITICALCVSS 3.1
Unknownknown ransomware use
188days from NVD publication to KEV
What it is
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.
| CWE | CWE-22 |
|---|---|
| CVSS vector | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H |
| NVD published | 2021-04-29 (Analyzed) |
Original records: NVD · CISA KEV · JSON: /api/cve/CVE-2021-20090.json · all KEV CVEs
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Get the full file: Exploited Vulnerabilities Brief – September 2026 ($29): this month's KEV additions ranked by EPSS, ransomware use and due date, ready to hand to a patch team. Checkout by Polar.