What’s Vulnerable › Vulnerabilities

CVE-2026-22892: Insufficient Authorization in Mattermost Jira Plugin Allows Unauthorized Access to Post Attachments

• Severity: medium (CVSS 4.3 v3.1)
• Exploited in the wild: not listed in CISA KEV
• EPSS: 0.3% probability of exploitation in the next 30 days
• Public exploit or detection template: none known
• Published: 2026-02-13 · updated 2026-06-17
• Weakness: CWE-863

Description

Mattermost versions 11.1.x <= 11.1.2, 10.11.x <= 10.11.9, 11.2.x <= 11.2.1 fail to validate user permissions when creating Jira issues from Mattermost posts, which allows an authenticated attacker with access to the Jira plugin to read post content and attachments from channels they do not have access to via the /create-issue API endpoint by providing the post ID of an inaccessible post.. Mattermost Advisory ID: MMSA-2025-00550

Affected products

• Mattermost: from 10.11.0 before 10.11.10; from 11.0.0 before 11.1.3; from 11.2.0 before 11.2.2 — fixed in 10.11.10, 11.1.3, 11.2.2

How to fix

Upgrade to a fixed version: Mattermost 10.11.10, 11.1.3, 11.2.2. Check the vendor advisory for mitigations.

References

• https://mattermost.com/security-updates

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