CVE-2025-9078

Weak cache keys lead to post IDOR and link preview poisoning

State: Published
Severity: 4.3 Medium
Published: Sep 15, 2025
Updated: Sep 15, 2025
Reserved: Aug 15, 2025

Description

Mattermost versions 10.8.x <= 10.8.3, 10.5.x <= 10.5.8, 9.11.x <= 9.11.17, 10.10.x <= 10.10.1, 10.9.x <= 10.9.3 fail to properly validate cache keys for link metadata which allows authenticated users to access unauthorized posts and poison link previews via hash collision attacks on FNV-1 hashing

Scores

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

Weaknesses

CWE-328 Use of Weak Hash

Affected Products

Product	Versions
MattermostMattermost	10.8.0 through 10.8.3Affected 10.5.0 through 10.5.8Affected 9.11.0 through 9.11.17Affected 10.10.0 through 10.10.1Affected 10.9.0 through 10.9.3Affected 10.11.0Not affected 10.8.4Not affected 10.5.9Not affected 9.11.18Not affected 10.10.2Not affected 10.9.4Not affected

References

https://mattermost.com/security-updates

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