Description

Backstage is an open platform for building developer portals. The Backstage scaffolder-backend plugin uses a templating library that requires 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. 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. This is vulnerability is fixed in version 1.15.0 of `@backstage/plugin-scaffolder-backend`.

Classification

CVE ID: CVE-2023-35926

CVSS Base Severity: HIGH

CVSS Base Score: 8.1

Affected Products

Vendor: backstage

Product: backstage

Exploit Prediction Scoring System (EPSS)

EPSS Score: 0.64% (probability of being exploited)

EPSS Percentile: 79.33% (scored less or equal to compared to others)

EPSS Date: 2025-02-03 (when was this score calculated)

References

https://github.com/backstage/backstage/security/advisories/GHSA-wg6p-jmpc-xjmr
https://github.com/backstage/backstage/commit/fb7375507d56faedcb7bb3665480070593c8949a
https://github.com/backstage/backstage/releases/tag/v1.15.0

Timeline