CVE-2021-41151 Explained : Impact and Mitigation

Backstage is an open platform for building developer portals. In affected versions, a malicious actor could read sensitive files from the environment where Scaffolder Tasks are run. The vulnerability is mitigated by the fact that an attacker would need access to create and register templates in the Backstage catalog.

Understanding CVE-2021-41151

What is CVE-2021-41151?

CVE-2021-41151 is a vulnerability in the

@backstage/plugin-scaffolder-backend

of Backstage, allowing a malicious actor to read sensitive files by crafting a custom Scaffolder template.

The Impact of CVE-2021-41151

The vulnerability has a base CVSS score of 6.8 (Medium severity) with high confidentiality impact. The attack complexity is low, requiring high privileges, and does not affect availability or integrity.

Technical Details of CVE-2021-41151

Vulnerability Description

A malicious actor can read sensitive files by crafting a custom Scaffolder template.

Affected Systems and Versions

Product: Backstage
Vendor: Backstage
Versions: >=0.9.4, < 0.15.9

Exploitation Mechanism

Crafting a custom Scaffolder template with a specific action and source path to include sensitive files in a pull request.

Mitigation and Prevention

Immediate Steps to Take

Update to version

0.15.9

of

@backstage/plugin-scaffolder-backend

to patch the vulnerability.

Long-Term Security Practices

Monitor and restrict template creation and registration in the Backstage catalog.
Regularly review and audit templating actions and paths.

Patching and Updates

Ensure timely installation of patches and updates to stay protected.