Security advisory
@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.
- Products
- Not specified
- Affected versions
- Not specified
- Fixed versions
- Not specified
- CVEs
- CVE-2021-43783
- Confirmed fixed CVEs
- Not specified
- Updated in this feed
- 31 Oct 2026, 12:00 UTC · Revision 1
Source evidence
@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.
osv:CVE-2021-43783
Complete source record
{
"id": "35930b281c0b569eaf76cb542f8bc7fb449fe0b97cf42c1aa8b00abeb7a41833",
"url": "https://osv.dev/vulnerability/CVE-2021-43783",
"method": "structured",
"payload": {
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"title": "CVE-2021-43783",
"summary": "@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.",
"evidence": "osv:CVE-2021-43783",
"products": [],
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"provider": "osv",
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"source_id": "core-osv",
"document_id": 386798,
"published_at": "2021-11-29T20:15:08.077+00:00"
}