CVE-2026-1629 PUBLISHED

Permalink Preview Information Disclosure After Permission Revocation

Assigner: Mattermost
Reserved: 29.01.2026 Published: 16.03.2026 Updated: 17.03.2026

Mattermost versions 10.11.x <= 10.11.10 Fail to invalidate cached permalink preview data when a user loses channel access which allows the user to continue viewing private channel content via previously cached permalink previews until cache reset or relogin.. Mattermost Advisory ID: MMSA-2026-00580

Metrics

CVSS 3.1

CVSS Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:N
CVSS Score: 4.3

Attack Vector	Network	Scope	Unchanged
Attack Complexity	Low	Confidentiality Impact	Low
Privileges Required	Low	Integrity Impact	None
User Interaction	None	Availability Impact	None

CVSS 3.1

Product Status

Vendor	Mattermost
Product	Mattermost
Versions	Default: unaffected affected from 10.11.0 to 10.11.10 (incl.) Version 11.4.0 is unaffected Version 10.11.11 is unaffected

Solutions

Update Mattermost to versions 11.4.0, 10.11.11 or higher.

Credits

Joshua Rogers finder

References

MMSA-2026-00580

Problem Types

CWE-672: Operation on a Resource after Expiration or Release CWE