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
CWE
  • CWE-201 - Insertion of Sensitive Information Into Sent Data
Assigner
References
Impacted products
Vendor Product Version
Mattermost Mattermost Affected: 11.3.0 , ≤ 11.3.0 (semver)
Unaffected: 11.4.0
Unaffected: 11.3.1
Create a notification for this product.
Credits
Joshua Rogers
Show details on NVD website
To clipboard 

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  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
  • Confirmed: The vulnerability has been validated from an analyst's perspective.
  • Published Proof of Concept: A public proof of concept is available for this vulnerability.
  • Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
  • Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
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  • Not confirmed: The user expressed doubt about the validity of the vulnerability.
  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.



Detection rules are retrieved from Rulezet.