Summary
RCE vulnerability affecting v1beta3 templates in @backstage/plugin-scaffolder-backend
The templating library used by the scaffolder backend assumes that templates are trusted which is an undesired property of the scaffolder-backend. This has now been mitigated by sandboxing the template code execution.
For more information
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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.
Affected versions
Security releases
Kodem intelligence
Severity tells you how bad this could be in the worst case. It does not tell you whether you are exposed. Exploitability and impact are functions of runtime truth: whether the vulnerable code is present, reachable, and actually executes in your application. A vulnerable package can sit in your dependency tree and never run.
Kodem, an Intelligent Application Security platform, uses runtime intelligence to reveal which vulnerabilities actually execute in production, so teams prioritize the ones that genuinely matter. Kodem's runtime-powered SCA identifies whether this CVE is reachable in your applications.
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This is vulnerability is patched in version 0.15.14 of @backstage/plugin-scaffolder-backend.
Frequently Asked Questions
- What is GHSA-2G8G-63J4-9W3R? GHSA-2G8G-63J4-9W3R is a high-severity security vulnerability in @backstage/plugin-scaffolder-backend (npm), affecting versions < 0.15.14. It is fixed in 0.15.14.
- Which versions of @backstage/plugin-scaffolder-backend are affected by GHSA-2G8G-63J4-9W3R? @backstage/plugin-scaffolder-backend (npm) versions < 0.15.14 is affected.
- Is there a fix for GHSA-2G8G-63J4-9W3R? Yes. GHSA-2G8G-63J4-9W3R is fixed in 0.15.14. Upgrade to this version or later.
- Is GHSA-2G8G-63J4-9W3R exploitable, and should I be worried? Whether GHSA-2G8G-63J4-9W3R is exploitable in your environment depends on whether the vulnerable code is present and reachable. A CVSS score is a worst-case rating; it does not account for your specific deployment, configuration, or usage patterns. Kodem, an Intelligent Application Security platform, uses runtime intelligence to show which vulnerabilities actually execute in production, so you can focus on the ones that represent real risk. Get a demo
- What actually determines whether GHSA-2G8G-63J4-9W3R is exploitable, and how bad it is? Exploitability and impact are not fixed properties of a CVE. They depend on runtime truth: whether the vulnerable code is present, reachable, and actually executes in your application. A high CVSS score on a dependency that never runs is not the same as real risk. Kodem, an Intelligent Application Security platform, uses runtime intelligence to reveal which vulnerabilities actually execute in production, so teams prioritize the ones that genuinely matter.
- How do I fix GHSA-2G8G-63J4-9W3R? Upgrade
@backstage/plugin-scaffolder-backendto 0.15.14 or later.