CVE-2026-2578 - Vulnerability Details - OpenCVE

Mattermost versions 11.3.x <= 11.3.0 fail to preserve the redacted state of burn-on-read posts during deletion which allows channel members to access unrevealed burn-on-read message contents via the WebSocket post deletion event.. Mattermost Advisory ID: MMSA-2026-00579

No CVSS v4.0

Attack Vector Network

Attack Complexity Low

Privileges Required Low

Scope Unchanged

Confidentiality Impact Low

Integrity Impact None

Availability Impact None

User Interaction None

No CVSS v3.0

No CVSS v2

This CVE is not in the KEV list.

No EPSS score available.

Exploitation none

Automatable no

Technical Impact partial

No data.

No data.

No data.

No data.

Advisories

No advisories yet.

Fixes

Solution

Update Mattermost to versions 11.4.0, 11.3.1 or higher.

Workaround

No workaround given by the vendor.

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 12:15:00 +0000

Type	Values Removed	Values Added
Description		Mattermost versions 11.3.x <= 11.3.0 fail to preserve the redacted state of burn-on-read posts during deletion which allows channel members to access unrevealed burn-on-read message contents via the WebSocket post deletion event.. Mattermost Advisory ID: MMSA-2026-00579
Title		Information Disclosure via WebSocket Event When Deleting Unrevealed Burn on Read Posts
Weaknesses		CWE-201
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:L/I:N/A:N'}`

Projects

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MITRE

Status: PUBLISHED

Assigner: Mattermost

Published: 2026-03-16T11:58:09.834Z

Updated: 2026-03-16T13:49:55.812Z

Reserved: 2026-02-16T10:09:16.281Z

Link: CVE-2026-2578

Vulnrichment

Updated: 2026-03-16T13:43:46.276Z

NVD

Status : Awaiting Analysis

Published: 2026-03-16T14:19:30.840

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

Link: CVE-2026-2578

Redhat

No data.

OpenCVE Enrichment

No data.

Weaknesses

CWE-201

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