Which versions of Buffalo Wi Fi Router Products are affected by CVE-2026-27650?

BUFFALO Wi-Fi router models contain a remote command injection vulnerability (CVSS 8.8) that enables unauthenticated attackers to execute arbitrary operating system commands, potentially compromising…

How to fix or mitigate CVE-2026-27650?

Within 24 hours: Identify and inventory all BUFFALO Wi-Fi router models in production using network discovery tools and cross-reference against official BUFFALO CPE advisory listings. Within 7 days: Isolate affected routers to a monitored network segment; document business criticality and failover options for each device; contact BUFFALO support for patch availability timeline and interim guidance. Within 30 days: Implement network segmentation to restrict router administrative access to authorized personnel only; deploy compensating controls (see below); establish a contingency plan for device replacement if patches remain unavailable.

Buffalo Wi Fi Router Products CVE-2026-27650

Q: What is the CVSS score of CVE-2026-27650?

CVE-2026-27650 has a CVSS 4.0 base score of 8.6 (High). CVSS vector: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:A/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X. EPSS exploitation probability: 0.1%.

EUVD-2026-16543 HIGH

OS Command Injection (CWE-78)

2026-03-27 jpcert

Command Injection Buffalo Wi Fi Router Products

8.6

CVSS 4.0 · NVD

Severity by source

NVD PRIMARY

8.6 HIGH

CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:A/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X

Primary rating from NVD · only source for this CVE.

CVSS VectorNVD

CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:A/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X

Attack Vector

Network

Attack Complexity

Low

Privileges Required

None

User Interaction

Scope

Lifecycle Timeline

EUVD ID Assigned

Mar 27, 2026 - 06:00 euvd

EUVD-2026-16543

Analysis Generated

Mar 27, 2026 - 06:00 vuln.today

CVE Published

Mar 27, 2026 - 05:24 nvd

HIGH 8.6

DescriptionCVE.org

OS Command Injection vulnerability exists in BUFFALO Wi-Fi router products. If this vulnerability is exploited, an arbitrary OS command may be executed on the products.

AnalysisAI

Remote OS command injection in BUFFALO Wi-Fi router products allows unauthenticated attackers to execute arbitrary operating system commands with user interaction required. The vulnerability affects multiple BUFFALO Wi-Fi router models as confirmed by CPE designation and carries a CVSS score of 8.8 (High severity). While attack complexity is low and no privileges are required, successful exploitation depends on user interaction, reducing immediate attack surface. No public exploit identified at time of analysis, and exploitation probability metrics are not available in provided intelligence.

Technical ContextAI

This vulnerability is classified as CWE-78 (Improper Neutralization of Special Elements used in an OS Command), commonly known as OS command injection. The affected technology comprises BUFFALO Inc.'s Wi-Fi router product line (CPE: cpe:2.3:a:buffalo_inc.:buffalo_wi-fi_router_products). Command injection occurs when an application passes unsafe user-supplied data to a system shell without proper validation or sanitization, allowing attackers to inject shell metacharacters and execute arbitrary commands with the privileges of the vulnerable process. In network devices like routers, this typically manifests through web management interfaces, configuration APIs, or network service handlers that fail to sanitize input parameters before passing them to underlying system calls or shell commands.

RemediationAI

Consult the official BUFFALO security advisory at https://www.buffalo.jp/news/detail/20260323-01.html for model-specific firmware updates and patch deployment instructions. The vendor advisory published March 23, 2026, contains detailed remediation guidance including affected firmware versions and patched release information. Until firmware updates can be applied, implement defense-in-depth measures including: restricting router management interface access to trusted internal networks only (disable WAN-side administration), implementing strong administrator credentials, educating administrators about phishing and social engineering risks given the UI:R requirement, and monitoring router logs for suspicious command execution patterns. Additional technical details and mitigation recommendations are available in the JVN advisory at https://jvn.jp/en/jp/JVN83788689/ published by JPCERT.