CVE-2021-27938
MEDIUMCVE-2021-27938 is a medium-severity (CVSS 6.1) Cross-site Scripting (XSS) vulnerability in symbiote/silverstripe-queuedjobs. O3 Security confirms whether CVE-2021-27938 is actually reachable in your code before you act, and blocks exploitation at runtime until you patch.
XSS in CreateQueuedJobTask
Real-World Exposure
symbiote/silverstripe-queuedjobs🐘symbiote/silverstripe-queuedjobs🐘symbiote/silverstripe-queuedjobs🐘symbiote/silverstripe-queuedjobs🐘symbiote/silverstripe-queuedjobs🐘symbiote/silverstripe-queuedjobs🐘symbiote/silverstripe-queuedjobs🐘symbiote/silverstripe-queuedjobs+1 moreReal-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
A vulnerability has been identified in the Silverstripe CMS 3 and 4 version of the symbiote/silverstripe-queuedjobs module. A Cross Site Scripting vulnerability allows an attacker to inject an arbitrary payload in the CreateQueuedJobTask dev task via a specially crafted URL.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 🐘Packagist | symbiote/silverstripe-queuedjobs | ≥ 3.0.0&&< 3.0.2 | 3.0.2 |
| 🐘Packagist | symbiote/silverstripe-queuedjobs | ≥ 3.1.0&&< 3.1.4 | 3.1.4 |
| 🐘Packagist | symbiote/silverstripe-queuedjobs | ≥ 4.0.0&&< 4.0.7 | 4.0.7 |
| 🐘Packagist | symbiote/silverstripe-queuedjobs | ≥ 4.1.0&&< 4.1.2 | 4.1.2 |
| 🐘Packagist | symbiote/silverstripe-queuedjobs | ≥ 4.2.0&&< 4.2.4 | 4.2.4 |
| 🐘Packagist | symbiote/silverstripe-queuedjobs | ≥ 4.3.0&&< 4.3.3 | 4.3.3 |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for symbiote/silverstripe-queuedjobs. 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 symbiote/silverstripe-queuedjobs to 3.0.2 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2021-27938 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-2021-27938 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-2021-27938. 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-2021-27938 in your dependencies?
O3 detects CVE-2021-27938 across Packagist dependencies and uses function-level reachability to confirm whether the vulnerable code path is actually reachable — not just present. No false positives.