CVE-2026-2578 (GCVE-0-2026-2578)

Vulnerability from cvelistv5 – Published: 2026-03-16 11:58 – Updated: 2026-03-16 13:49
VLAI
Title
Information Disclosure via WebSocket Event When Deleting Unrevealed Burn on Read Posts
Summary
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
Severity
4.3 (Medium)
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:N
SSVC
Exploitation: none Automatable: no Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-03-16 13:42 UTC
CWE
  • CWE-201 - Insertion of Sensitive Information Into Sent Data
Assigner
Mattermost CNA under the mitre root
CNA scorecard B 80/100 over 122 records in the last 180 days details
References
URL Tags
https://mattermost.com/security-updates vendor-advisory
Impacted products
Vendor Product Version CPE status
Mattermost Mattermost Affected: 11.3.0 , ≤ 11.3.0 (semver)
Unaffected: 11.4.0
Unaffected: 11.3.1
guessed Create a notification for this product.
Credits
Joshua Rogers
Show details on NVD website
To clipboard 

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