High severity · published Nov 29, 2021
CVE-2021-43783
@backstage/plugin-scaffolder-backend is the backend for the default Backstage software templates
8.5
CVSS
1.2%
EPSS
No
On KEV
Description
@backstage/plugin-scaffolder-backend is the backend for the default Backstage software templates. In affected versions a malicious actor with write access to a registered scaffolder template is able to manipulate the template in a way that writes files to arbitrary paths on the scaffolder-backend host instance. This vulnerability can in some situation also be exploited through user input when executing a template, meaning you do not need write access to the templates. This method will not allow the attacker to control the contents of the injected file however, unless the template is also crafted in a specific way that gives control of the file contents. This vulnerability is fixed in version `0.15.14` of the `@backstage/plugin-scaffolder-backend`. This attack is mitigated by restricting access and requiring reviews when registering or modifying scaffolder templates.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:N/I:H/A:L
Attack vector
Network
Complexity
Low
Privileges
Low
User interaction
None
Confidentiality
None
Integrity
High
Availability
Low
Scope
Changed
Exploitation
Is it being used?
Exploit prediction (EPSS)1.2% · higher than 69% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
BA
Backstage · Linuxfoundation
before 0.15.14 · source: NVD
Affected product
BA
Backstage
Linuxfoundation
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