CVE-2021-3297 - Vulnerability Details - OpenCVE

Description

On Zyxel NBG2105 V1.00(AAGU.2)C0 devices, setting the login cookie to 1 provides administrator access.

Published: 2021-01-26

Score: 7.8 High

EPSS: 80.5% High

KEV: No

Impact:

Action:

Analysis

Analysis and contextual insights are available on OpenCVE Cloud.

Default status is the baseline for the product, each version can override it (e.g. patched versions marked unaffected).

Vendor Product Default status Versions

n/a

n/a

affected

Version	Status	Constraints
`n/a`	affected	—

Configuration 1 [-]

AND

cpe:2.3:o:zyxel:nbg2105_firmware:v1.00\(aagu.2\)c0:*:*:*:*:*:*:*

cpe:2.3:h:zyxel:nbg2105:-:*:*:*:*:*:*:*

No data.

No data available yet.

Remediation

No vendor fix or workaround currently provided.

Additional remediation guidance may be available on OpenCVE Cloud.

Tracking

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Advisories

No advisories yet.

No CVSS v4.0

Attack Vector Local

Attack Complexity Low

Privileges Required Low

Scope Unchanged

Confidentiality Impact High

Integrity Impact High

Availability Impact High

User Interaction None

No CVSS v3.0

Access Vector Local

Access Complexity Low

Authentication None

Confidentiality Impact Complete

Integrity Impact Complete

Availability Impact Complete

This CVE is not in the KEV list.

The EPSS score is 0.80545.

Key SSVC decision points have not yet been added.

References

Link	Providers
https://codeberg.org/nieldk/vulnerabilities/src/branch/main/zyxel%20nbg2105/Admin%20bypass
https://github.com/nieldk/vulnerabilities/blob/main/zyxel%20nbg2105/Admin%20bypass
https://www.zyxel.com/support/SupportLandingSR.shtml?c=gb&l=en&kbid=M-01490&md=NBG2105
https://www.zyxel.com/us/en/support/security_advisories.shtml

History

Tue, 25 Nov 2025 17:45:00 +0000

Type	Values Removed	Values Added
References		https://codeberg.org/nieldk/vulnerabilities/src/branch/main/zyxel%20nbg2105/Admin%20bypass

Subscriptions

Zyxel Nbg2105 Nbg2105 Firmware

MITRE

Status: PUBLISHED

Assigner: mitre

Published: 2021-01-26T07:11:41.000Z

Updated: 2025-11-25T17:27:20.441Z

Reserved: 2021-01-25T00:00:00.000Z

Link: CVE-2021-3297

Vulnrichment

No data.

NVD

Status : Modified

Published: 2021-01-26T18:16:29.770

Modified: 2025-11-25T18:15:48.173

Link: CVE-2021-3297

Redhat

No data.

OpenCVE Enrichment

No data.

Weaknesses

CWE-287

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