Coverage › CVE-2021-20090
CVE-2021-20090 Unmapped
Arcadyan Buffalo Firmware Path Traversal Vulnerability
- Vendor / product
- Arcadyan — Buffalo Firmware
- Description (CISA)
- 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.
- Added to KEV
- 2021-11-03
- Due date
- 2021-11-17
- Required action
- Apply updates per vendor instructions.
- Known ransomware use
- Unknown
- CWE
- CWE-22
- CISA notes
- https://nvd.nist.gov/vuln/detail/CVE-2021-20090
- Elsewhere
- cve.org · NVD · CISA KEV · JSON
ATT&CK techniques
No public source states how this vulnerability is exploited in ATT&CK terms.
The only authoritative CVE → ATT&CK mapping in the open — CTID's Mappings Explorer, pinned to a KEV snapshot of 2025-07-28 and ATT&CK 16.1 — does not include CVE-2021-20090. CISA's catalogue carries no technique field. kevmap does not infer techniques from the CWE (CWE-22) — here is why — and does not guess.
This page will change state automatically if a mapping is published. What is shown above is everything CISA publishes about the entry.
Sigma rules tagged with this CVE
1 rule in SigmaHQ carries the tag cve.2021-20090. These are shown as detection content for the CVE itself. Their ATT&CK tags are deliberately not rendered here: a rule author's tag is not an authoritative statement of how the vulnerability is exploited, and this page does not show techniques for unmapped entries.