๐Ÿ” CVE Alert

CVE-2026-2578

MEDIUM 4.3

Information Disclosure via WebSocket Event When Deleting Unrevealed Burn on Read Posts

CVSS Score
4.3
EPSS Score
0.0%
EPSS Percentile
0th

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

CWE CWE-201
Vendor mattermost
Product mattermost
Published Mar 16, 2026
Last Updated Mar 16, 2026
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CVSS v3 Breakdown

CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:N
Attack Vector
Network
Attack Complexity
Low
Privileges Required
Low
User Interaction
None
Scope
Unchanged
Confidentiality
Low
Integrity
None
Availability
None

Affected Versions

Mattermost / Mattermost
11.3.0 โ‰ค 11.3.0

References

NVD โ†— CVE.org โ†— EPSS Data โ†—
mattermost.com: https://mattermost.com/security-updates

Credits

Joshua Rogers