CVE-2021-37859

Reflected XSS in OAuth Flow

View on CVE.org

Published Aug 5, 2021 CVSS 3.1 · 7.1 High EPSS 3.3% KEV · Not listed

Description

Fixed a bypass for a reflected cross-site scripting vulnerability affecting OAuth-enabled instances of Mattermost.

Affected Products

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

Vendor Product Default status Versions

Mattermost

Mattermost

affected

Version	Status	Constraints
`5.34.5`	unaffected	—
`5.35.4`	unaffected	—
`5.32.0`	affected	≤ 5.36.0

Configuration 1 [-]

OR	cpe:2.3:a:mattermost:mattermost::::::::
	cpe:2.3:a:mattermost:mattermost::::::::
	cpe:2.3:a:mattermost:mattermost::::::::

No data.

No data available yet.

Remediation

No solution or workaround provided in the CVE record

Tracking

Sign in to view the affected projects.

Advisories

No advisories available

Metrics

No CVSS v4.0

Attack Vector Network

Attack Complexity High

Privileges Required None

Scope Unchanged

Confidentiality Impact High

Integrity Impact High

Availability Impact Low

User Interaction Required

No CVSS v3.0

Access Vector Network

Access Complexity Medium

Authentication None

Confidentiality Impact None

Integrity Impact Partial

Availability Impact None

This CVE is not in the KEV list.

Exploit prediction score: 3.3% (3.288% probability within 30 days)

Key SSVC decision points have not yet been added.

References

Link	Providers
https://mattermost.com/security-updates/

History

No history.

Subscriptions

Mattermost Mattermost

Weaknesses

CWE-79

Sources

CVE record Updated: Aug 4, 2024, 1:30 AM

Status: PUBLISHED
Assigner: Mattermost
Published: Aug 5, 2021, 7:40 PM
Updated: Aug 4, 2024, 1:30 AM
Reserved: Aug 2, 2021, 12:00 AM

View source JSON

Vulnrichment No data

No data.

NVD Updated: Jun 17, 2026, 4:01 AM

Status: Modified
Published: Aug 5, 2021, 8:15 PM
Modified: Jun 17, 2026, 4:01 AM

View source JSON

Red Hat No data

No data.

OpenCVE enrichment No data

No data.

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