GHSA-ffx7-34p2-vm3w — mattermost-plugin-conflue…
HIGHGHSA-ffx7-34p2-vm3w is a high-severity (CVSS 7.7) Cross-site Scripting (XSS) vulnerability in github.com/mattermost/mattermost-plugin-confluence. A fix is available for github.com/mattermost/mattermost-plugin-confluence — see the affected versions and patch details below.
Mattermost Confluence plugin doesn't properly escape user-controlled display names in HTML template rendering
Exploitation Status
No confirmed exploitation observed yet
- CISA’s own triage has not observed active exploitation or public proof-of-concept code for this CVE as of its last assessment.
Exploitation and automatability from CISA’s SSVC triage for GHSA-ffx7-34p2-vm3w.
EPSS Exploitation Probability
Probability of exploitation in the next 30 days, from FIRST.org EPSS.
How urgent is this, really
GHSA-ffx7-34p2-vm3w by exploitation likelihood (EPSS) against impact (CVSS). Outside the shaded patch-first corner.
Where this sits among everything scored
Of 379,842 CVEs with a current EPSS score, this one falls in the < 10% band (highlighted). Counts from FIRST.org, log-scaled.
Real-World Exposure
github.com/mattermost/mattermost-plugin-confluenceReal-time download stats are indexed for npm and PyPI packages. This vulnerability affects Go packages — download data is not available via public APIs for these ecosystems.
Description
Mattermost Confluence plugin version < 1.7.0 fails to properly escape user-controlled display names in HTML template rendering which allows authenticated Confluence users with malicious display names to execute arbitrary JavaScript in victim browsers via sending a specially crafted OAuth2 connection link that, when visited, renders the attacker's display name without proper sanitization. Mattermost Advisory ID: MMSA-2025-00557
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 🐹Go | github.com/mattermost/mattermost-plugin-confluence | all versions | 1.7.0go get github.com/mattermost/mattermost-plugin-confluence@v1.7.0 |
Affected Products
confluencemattermostDetection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for github.com/mattermost/mattermost-plugin-confluence, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update github.com/mattermost/mattermost-plugin-confluence to 1.7.0 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-ffx7-34p2-vm3w is resolved across your whole dependency graph.
Workarounds
Escape or sanitise the affected output on the server side rather than relying on client-side filtering, and add a Content-Security-Policy that blocks inline script execution so injected markup cannot run even if it reaches the page.
Frequently Asked Questions
Is GHSA-ffx7-34p2-vm3w in your dependencies?
Find it across Go, including transitive dependencies.