CVE-2024-32939 — server
MEDIUMCVE-2024-32939 is a medium-severity (CVSS 4.3) CWE-284 vulnerability in github.com/mattermost/mattermost/server/v8. A fix is available for github.com/mattermost/mattermost/server/v8 — see the affected versions and patch details below.
Email addresses of remote users visible in props regardless of server settings
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 CVE-2024-32939.
EPSS Exploitation Probability
Probability of exploitation in the next 30 days, from FIRST.org EPSS.
How urgent is this, really
Where this sits among everything scored
Real-World Exposure
github.com/mattermost/mattermost/server/v8🐹github.com/mattermost/mattermost/server/v8🐹github.com/mattermost/mattermost/server/v8🐹github.com/mattermost/mattermost/server/v8Real-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 versions 9.9.x <= 9.9.1, 9.5.x <= 9.5.7, 9.10.x <= 9.10.0, 9.8.x <= 9.8.2, when shared channels are enabled, fail to redact remote users' original email addresses stored in user props when email addresses are otherwise configured not to be visible in the local server."
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 🐹Go | github.com/mattermost/mattermost/server/v8 | ≥ 9.9.0&&< 9.9.2 | 9.9.2go get github.com/mattermost/mattermost/server/v8@v9.9.2 |
| 🐹Go | github.com/mattermost/mattermost/server/v8 | ≥ 9.5.0&&< 9.5.8 | 9.5.8go get github.com/mattermost/mattermost/server/v8@v9.5.8 |
| 🐹Go | github.com/mattermost/mattermost/server/v8 | ≥ 9.10.0&&< 9.10.1 | 9.10.1go get github.com/mattermost/mattermost/server/v8@v9.10.1 |
| 🐹Go | github.com/mattermost/mattermost/server/v8 | ≥ 9.8.0&&< 9.8.3 | 9.8.3go get github.com/mattermost/mattermost/server/v8@v9.8.3 |
Affected Products
mattermostmattermostDetection & 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/server/v8, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update github.com/mattermost/mattermost/server/v8 to 9.9.2 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2024-32939 is resolved across your whole dependency graph.
Workarounds
Put an independent control in front of the weakness: restrict the affected endpoint or interface to trusted networks, require an additional authentication factor or proxy-level check, and invalidate existing sessions and credentials in case the flaw has already been used.
Frequently Asked Questions
Is CVE-2024-32939 in your dependencies?
Find it across Go, including transitive dependencies.