Medium severity · published Oct 18, 2021
CVE-2021-41151
Backstage is an open platform for building developer portals
4.9
CVSS
1.3%
EPSS
No
On KEV
Description
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 attack is executed by crafting a custom Scaffolder template with a `github:publish:pull-request` action and a particular source path. When the template is executed the sensitive files would be included in the published pull request. This vulnerability is mitigated by the fact that an attacker would need access to create and register templates in the Backstage catalog, and that the attack is very visible given that the exfiltration happens via a pull request. The vulnerability is patched in the `0.15.9` release of `@backstage/plugin-scaffolder-backend`.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:N/A:N
Attack vector
Network
Complexity
Low
Privileges
High
User interaction
None
Confidentiality
High
Integrity
None
Availability
None
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)1.3% · higher than 71% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
BA
Backstage · Linuxfoundation
0.9.4 before 0.15.9 · source: NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2021-41151
CVE.org
https://www.cve.org/CVERecord?id=CVE-2021-41151
Patch
https://github.com/backstage/backstage/commit/6968962c920508eae19a4c1c200fa2c8980a4006
Third Party Advisory
https://github.com/backstage/backstage/security/advisories/GHSA-pvv8-8fx9-h673
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