GHSA-8jhh-3jf2-pfwr
MEDIUMGHSA-8jhh-3jf2-pfwr is a medium-severity (CVSS 6.5) Information Exposure vulnerability in github.com/mattermost/mattermost-server. O3 Security confirms whether GHSA-8jhh-3jf2-pfwr is actually reachable in your code before you act, and blocks exploitation at runtime until you patch.
Mattermost vulnerable to information disclosure
Blast Radius
github.com/mattermost/mattermost-server🐹github.com/mattermost/mattermost-server🐹github.com/mattermost/mattermost-server🐹github.com/mattermost/mattermost-server/v5🐹github.com/mattermost/mattermost-server/v6Real-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
When running in a High Availability configuration, Mattermost fails to sanitize some of the user_updated and post_deleted events broadcast to all users, leading to disclosure of sensitive information to some of the users with currently connected Websocket clients.
Issue Identifier: MMSA-2023-00138
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 🐹Go | github.com/mattermost/mattermost-server | ≥ 3.3.0&&< 7.1.6 | 7.1.6 |
| 🐹Go | github.com/mattermost/mattermost-server | ≥ 7.7.0&&< 7.7.2 | 7.7.2 |
| 🐹Go | github.com/mattermost/mattermost-server | ≥ 7.1.0&&< 7.1.6 | 7.1.6 |
| 🐹Go | github.com/mattermost/mattermost-server/v5 | ≥ 5.0.0&&< 7.1.6 | 7.1.6 |
| 🐹Go | github.com/mattermost/mattermost-server/v6 | ≥ 6.0.0&&< 7.1.6 | 7.1.6 |
Detection & 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. O3's reachability analysis confirms whether the vulnerable code path is actually invoked in your application, so you act on real exposure instead of every transitive match.
Fix
Update github.com/mattermost/mattermost-server to 7.1.6 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-8jhh-3jf2-pfwr is resolved across your whole dependency graph.
Workarounds
If you can't upgrade right away: gate or disable the affected feature, validate untrusted input at the boundary, and avoid passing attacker-controlled data into the vulnerable path. O3's runtime protection blocks exploitation in production as an interim safeguard until the upgrade lands.
How O3 protects you
O3 pinpoints whether GHSA-8jhh-3jf2-pfwr is reachable in your code and exactly where to fix it, then blocks exploitation in production at runtime until the patched version is deployed.
Tailored to GHSA-8jhh-3jf2-pfwr. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.
Frequently Asked Questions
Is GHSA-8jhh-3jf2-pfwr in your dependencies?
O3 detects GHSA-8jhh-3jf2-pfwr across Go dependencies and uses function-level reachability to confirm whether the vulnerable code path is actually reachable — not just present. No false positives.