GHSA-wg6p-jmpc-xjmr is a high-severity (CVSS 8) Code Injection vulnerability in @backstage/plugin-scaffolder-backend. A fix is available for @backstage/plugin-scaffolder-backend — see the affected versions and patch details below.
Backstage Scaffolder plugin has insecure sandbox
Exploitation Status
No confirmed exploitation observed yet
- A successful exploit gives an attacker total control of the affected component, not partial access.
- 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-wg6p-jmpc-xjmr.
EPSS Exploitation Probability
EPSS (Exploit Prediction Scoring System) is a daily probability model maintained by FIRST.org. It estimates the likelihood a CVE will be exploited in production environments within the next 30 days, derived from real-world threat intelligence signals.
How urgent is this, really
GHSA-wg6p-jmpc-xjmr plotted by exploitation likelihood (EPSS) against impact (CVSS). The shaded corner — EPSS 50%+ and CVSS 7.0+ — is where this CVE doesn't sit, though severity or exploitability alone can still warrant action.
Where this sits among everything scored
Of 377,238 CVEs with a current EPSS score, this one falls in the < 10% band (highlighted). Real counts from FIRST.org, not a sample — log-scaled since the landscape is heavily right-skewed.
Real-World Exposure
How broadly this vulnerability is actually deployed: weekly install volume shows current usage, and reverse-dependency count shows how many other packages break if it stays unpatched.
@backstage/plugin-scaffolder-backendnpmDescription
The Backstage scaffolder-backend plugin uses a templating library that requires a sandbox, as it by design allows for code injection. The library used for this sandbox so far has been vm2, but in light of several past vulnerabilities and existing vulnerabilities that may not have a fix, the plugin has switched to using a different sandbox library.
Impact
A malicious actor with write access to a registered scaffolder template could manipulate the template in a way that allows for remote code execution on the scaffolder-backend instance. This was only exploitable in the template YAML definition itself and not by user input data.
Patches
This is vulnerability is fixed in version 1.15.0 of @backstage/plugin-scaffolder-backend.
Workarounds
Note that the Backstage Threat Model states that scaffolder templates are considered to be a sensitive area that with the recommendation that you control access and perform manual reviews of changes to the scaffolder templates. The exploit is of a nature where it is easily discoverable in manual review.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 📦npm | @backstage/plugin-scaffolder-backend | all versions | 1.15.0npm install @backstage/plugin-scaffolder-backend@1.15.0 |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for @backstage/plugin-scaffolder-backend, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update @backstage/plugin-scaffolder-backend to 1.15.0 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-wg6p-jmpc-xjmr 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 Security's impact-aware SCA analyses which vulnerable code paths your application actually calls, so a match like GHSA-wg6p-jmpc-xjmr can be triaged on real exposure rather than presence alone.
Tailored to GHSA-wg6p-jmpc-xjmr. 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-wg6p-jmpc-xjmr in your dependencies?
O3 Security finds GHSA-wg6p-jmpc-xjmr across npm dependencies, including transitive ones, and its impact-aware SCA ranks findings by whether your code actually calls the vulnerable path.