Description
Mattermost versions 11.1.x <= 11.1.0, 11.0.x <= 11.0.5, 10.12.x <= 10.12.3, 10.11.x <= 10.11.7 fail to verify that post actions invoking /share-issue-publicly were created by the Jira plugin which allowed a malicious Mattermost user to exfiltrate Jira tickets when victim users interacted with affected posts
Affected products
mattermost: mattermost server
References1
- mattermost.com/security-updates Vendor Advisory
Metrics
- CVSS 3.1
-
4.1
MEDIUM
Score source: NVD
CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:N/A:N - EPSS — exploit probability
- 0% percentile: 7 · as of 11 November 2026
- CWE
- CWE-863
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