CVE-2026-0999 (GCVE-0-2026-0999)

Vulnerability from cvelistv5 – Published: 2026-02-16 09:47 – Updated: 2026-02-17 16:53
VLAI?
Title
Authentication bypass via userID login when email and username login are disabled
Summary
Mattermost versions 11.1.x <= 11.1.2, 10.11.x <= 10.11.9, 11.2.x <= 11.2.1 fail to properly validate login method restrictions which allows an authenticated user to bypass SSO-only login requirements via userID-based authentication. Mattermost Advisory ID: MMSA-2025-00548
Severity ?
5.4 (Medium)
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:N
CWE
  • CWE-303 - Incorrect Implementation of Authentication Algorithm
Assigner
References
Impacted products
Vendor Product Version
Mattermost Mattermost Affected: 11.1.0 , ≤ 11.1.2 (semver)
Affected: 10.11.0 , ≤ 10.11.9 (semver)
Affected: 11.2.0 , ≤ 11.2.1 (semver)
Unaffected: 11.3.0
Unaffected: 11.1.3
Unaffected: 10.11.10
Unaffected: 11.2.2
Create a notification for this product.
Credits
daw10
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.