CVE-2026-2457 - Vulnerability Details - OpenCVE

Mattermost versions 11.3.x <= 11.3.0, 11.2.x <= 11.2.2, 10.11.x <= 10.11.10 fail to sanitize client-supplied post metadata which allows an authenticated attacker to spoof permalink embeds impersonating other users via crafted PUT requests to the post update API endpoint.. Mattermost Advisory ID: MMSA-2025-00569

No CVSS v4.0

Attack Vector Network

Attack Complexity Low

Privileges Required Low

Scope Unchanged

Confidentiality Impact None

Integrity Impact Low

Availability Impact None

User Interaction None

No CVSS v3.0

No CVSS v2

This CVE is not in the KEV list.

The EPSS score is 0.00014.

Exploitation none

Automatable no

Technical Impact partial

No data.

No data.

No data.

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References

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

History

Mon, 16 Mar 2026 14:15:00 +0000

Type	Values Removed	Values Added
Metrics		ssvc `{'options': {'Automatable': 'no', 'Exploitation': 'none', 'Technical Impact': 'partial'}, 'version': '2.0.3'}`

Mon, 16 Mar 2026 11:45:00 +0000

Type	Values Removed	Values Added
Description		Mattermost versions 11.3.x <= 11.3.0, 11.2.x <= 11.2.2, 10.11.x <= 10.11.10 fail to sanitize client-supplied post metadata which allows an authenticated attacker to spoof permalink embeds impersonating other users via crafted PUT requests to the post update API endpoint.. Mattermost Advisory ID: MMSA-2025-00569
Title		WebSocket Message Spoofing via Permalink Embed Manipulation
Weaknesses		CWE-346
References		https://mattermost.com/security-updates
Metrics		cvssV3_1 `{'score': 4.3, 'vector': 'CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:N'}`

MITRE

Status: PUBLISHED

Assigner: Mattermost

Published: 2026-03-16T11:20:25.335Z

Updated: 2026-03-16T13:49:57.761Z

Reserved: 2026-02-13T11:06:55.712Z

Link: CVE-2026-2457

Vulnrichment

Updated: 2026-03-16T13:44:16.018Z

NVD

Status : Awaiting Analysis

Published: 2026-03-16T14:19:29.367

Modified: 2026-03-16T14:53:07.390

Link: CVE-2026-2457

Redhat

No data.

OpenCVE Enrichment

No data.

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