CVE-2026-2458 (GCVE-0-2026-2458)

Vulnerability from cvelistv5 – Published: 2026-03-16 11:27 – Updated: 2026-03-16 13:49
VLAI
Title
Unauthorized channel enumeration in private teams after member removal
Summary
Mattermost versions 11.3.x <= 11.3.0, 11.2.x <= 11.2.2, 10.11.x <= 10.11.10 fail to properly validate team membership when searching channels which allows a removed team member to enumerate all public channels within a private team via the channel search API endpoint.. Mattermost Advisory ID: MMSA-2025-00568
Severity
4.3 (Medium)
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:N
CWE
Assigner
References
URL Tags
https://mattermost.com/security-updates vendor-advisory
Impacted products
Vendor Product Version
Mattermost Mattermost Affected: 11.3.0 , ≤ 11.3.0 (semver)
Affected: 11.2.0 , ≤ 11.2.2 (semver)
Affected: 10.11.0 , ≤ 10.11.10 (semver)
Unaffected: 11.4.0
Unaffected: 11.3.1
Unaffected: 11.2.3
Unaffected: 10.11.11
Create a notification for this product.
Credits
0x7oda7123
Show details on NVD website
To clipboard 

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Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.

Sightings

Author Source Type Date Other

Nomenclature

  • 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.
  • Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
  • 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.