CVE-2021-20090

Arcadyan — Arcadyan Buffalo Firmware Path Traversal Vulnerability

CISA KEV · in the CISA KEV catalog since 2021-11-03

What EVULNABLE says

EVULNABLE Risk · priority 87/100 Immediate Intelligence coverage 75/90 — no pre-patch disclosure data
ExigentOverdue by 4.8 yearsCISA KEVActively Exploited

Why it matters: Listed in the CISA KEV catalog, and an EPSS probability of 0.999.

Out-of-Band / Urgent Remediation

The priority band answers “how soon”, not “how bad” — see Methodology for what it weighs and where it abstains.

The evidence behind it

Published measurements for CVE-2021-20090
MeasureValueSource
CVSS base score 9.8 NVD
FIRST EPSS 0.999 (99.98th pctl) FIRST
Actively exploited Confirmed CISA KEV
Ransomware campaign use Unknown or none CISA KEV
CISA remediation deadline 2021-11-17 — Overdue by 4.8 years CISA KEV
Intelligence coverage 75/90 — no pre-patch disclosure data

What CISA says to do

This page is an opinion about urgency. Where it and a source of record disagree, the source of record is the record.