CVE-2025-21088 - CVE House
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Status published Medium CVE-2025-21088

WebApp crash via improper validation of proto style in attachments

Vulnerability Description

Mattermost versions 10.2.x <= 10.2.0, 9.11.x <= 9.11.5, 10.0.x <= 10.0.3, 10.1.x <= 10.1.3 fail to properly validate the style of proto supplied to an action's style in post.props.attachments, which allows an attacker to crash the frontend via crafted malicious input.

Impact Analysis

Refer to official advisory for detailed impact metrics.

Remediation

Ensure systems are updated to the latest vendor-supplied patch levels.

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Credits & Attribution

The following person or organization is credited with identifying this vulnerability, as recorded in the NVD database:

  • c0rydoras

References

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Affected Vendor

Affected Software

Mattermost
Vulnerable Versions:
10.2.0, 9.11.0, 10.0.0, 10.1.0, 10.3.0, 10.2.1, 9.11.6, 10.0.4, 10.1.4

Timeline

Official Publish: January 15th, 2025
Last Modified: January 15th, 2025
Added to House: July 22nd, 2026

CVSS Vectors

V3: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

Weaknesses (CWE)

CWE-704

MITRE ATT&CK TTPs

No associated TTPs found for this vulnerability.