SOC status:Duty analyst on shift

UK Cyber Defence
VulnerabilityAnalyzed

CVE-2021-20090

Arcadyan Buffalo Firmware Path Traversal Vulnerability

KEVCRITICAL 9.8EPSS 100.0%

Does this matter?

Known to be exploited in the wild (CISA KEV, CISA remediation deadline 17 November 2021). Treat as an emergency change: patch or isolate now, then hunt for prior compromise.

Description

A path traversal vulnerability in the web interfaces of Buffalo WSR-2533DHPL2 firmware version <= 1.02 and WSR-2533DHP3 firmware version <= 1.24 could allow unauthenticated remote attackers to bypass authentication.

CVSS 3.1
9.8 CRITICALCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
EPSS
99.98% probability · 100th percentile
CISA KEV
Listed 3 November 2021 · due 17 November 2021
Weakness
CWE-22
Affected
buffalo/wsr-2533dhpl2-bk firmware · buffalo/wsr-2533dhp3-bk firmware
Source
vulnreport@tenable.com

CISA notes

Apply updates per vendor instructions. https://nvd.nist.gov/vuln/detail/CVE-2021-20090

Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.