What is the CVSS score of CVE-2026-21411?

CVE-2026-21411 has a CVSS 3.0 base score of 8.8 (High). CVSS vector: CVSS:3.0/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H. EPSS exploitation probability: 0.1%.

Which versions of OpenBlocks are affected by CVE-2026-21411?

Organizations using OpenBlocks series face significant risk from CVE-2026-21411 rated CVSS 8.8.

How to fix or mitigate CVE-2026-21411?

Within 7 days: Identify all affected systems running OpenBlocks series and apply vendor patches promptly. Monitor vendor channels for patch availability.

OpenBlocks CVE-2026-21411

HIGH

Authentication Bypass Using an Alternate Path or Channel (CWE-288)

2026-01-06 vultures@jpcert.or.jp

Authentication Bypass

8.8

CVSS 3.0 · NVD

Severity by source

NVD PRIMARY

8.8 HIGH

AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

Primary rating from NVD · only source for this CVE.

CVSS VectorNVD

CVSS:3.0/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

Attack Vector

Adjacent

Attack Complexity

Low

Privileges Required

None

User Interaction

None

Scope

Unchanged

Confidentiality

High

Integrity

High

Availability

High

Lifecycle Timeline

Analysis Generated

Mar 12, 2026 - 21:54 vuln.today

CVE Published

Jan 06, 2026 - 07:15 nvd

HIGH 8.8

DescriptionCVE.org

Authentication bypass issue exists in OpenBlocks series versions prior to FW5.0.8, which may allow an attacker to bypass administrator authentication and change the password.

AnalysisAI

OpenBlocks firmware versions before 5.0.8 contain an authentication bypass vulnerability that allows unauthenticated attackers on adjacent networks to gain administrator access and reset passwords without valid credentials. This high-severity flaw affects all OpenBlocks series devices and requires no user interaction to exploit, though no patch is currently available.

Technical ContextAI

Authentication bypass issue exists in OpenBlocks series versions prior to FW5.0.8, which may allow an attacker to bypass administrator authentication and change the password.