CVE-2021-40818 - Vulnerability Details - OpenCVE

Description

scheme/webauthn.c in Glewlwyd SSO server through 2.5.3 has a buffer overflow during FIDO2 signature validation in webauthn registration.

Published: 2021-09-08

Score: 9.8 Critical

EPSS: 1.5% Low

KEV: No

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 [-]

cpe:2.3:a:glewlwyd_sso_server_project:glewlwyd_sso_server:*:*:*:*:*:*:*:*

No data.

No data available yet.

Remediation

No solution or workaround provided in the CVE record.

Additional remediation guidance may be available on OpenCVE Cloud.

Tracking

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Advisories

Source	ID	Title
EUVD	EUVD-2021-27982	scheme/webauthn.c in Glewlwyd SSO server through 2.5.3 has a buffer overflow during FIDO2 signature validation in webauthn registration.

No CVSS v4.0

Attack Vector Network

Attack Complexity Low

Privileges Required None

Scope Unchanged

Confidentiality Impact High

Integrity Impact High

Availability Impact High

User Interaction None

No CVSS v3.0

Access Vector Network

Access Complexity Low

Authentication None

Confidentiality Impact Partial

Integrity Impact Partial

Availability Impact Partial

This CVE is not in the KEV list.

The EPSS score is 0.01492.

Key SSVC decision points have not yet been added.

References

Link	Providers
https://bugs.debian.org/993867
https://github.com/babelouest/glewlwyd/commit/0efd112bb62f566877750ad62ee828bff579b4e2

History

No history.

Subscriptions

Glewlwyd Sso Server Project Glewlwyd Sso Server

MITRE

Status: PUBLISHED

Assigner: mitre

Published: 2021-09-08T21:47:32.000Z

Updated: 2024-08-04T02:51:07.044Z

Reserved: 2021-09-08T00:00:00.000Z

Link: CVE-2021-40818

Vulnrichment

No data.

NVD

Status : Modified

Published: 2021-09-08T22:15:11.383

Modified: 2026-06-17T04:07:28.683

Link: CVE-2021-40818

Redhat

No data.

OpenCVE Enrichment

No data.

Weaknesses

CWE-120
Buffer Copy without Checking Size of Input ('Classic Buffer Overflow')

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