CVE-2021-27676 is a medium-severity (CVSS 5.4) Cross-site Scripting (XSS) vulnerability in centreon/centreon. O3 Security confirms whether CVE-2021-27676 is actually reachable in your code before you act, and blocks exploitation at runtime until you patch.
Cross-site scripting in Centreon
Real-World Exposure
centreon/centreonReal-time download stats are indexed for npm and PyPI packages. This vulnerability affects Packagist packages — download data is not available via public APIs for these ecosystems.
Description
Centreon version 20.10.2 is affected by a cross-site scripting (XSS) vulnerability. The dep_description (Dependency Description) and dep_name (Dependency Name) parameters are vulnerable to stored XSS. A user has to log in and go to the Configuration > Notifications > Hosts page.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 🐘Packagist | centreon/centreon | all versions | 20.10.7 |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for centreon/centreon. 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 centreon/centreon to 20.10.7 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2021-27676 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 CVE-2021-27676 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 CVE-2021-27676. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.
Frequently Asked Questions
Is CVE-2021-27676 in your dependencies?
O3 detects CVE-2021-27676 across Packagist dependencies and uses function-level reachability to confirm whether the vulnerable code path is actually reachable — not just present. No false positives.