Path Traversal in @backstage/plugin-scaffolder-backend (CVE-2021-43783)
Summary
Path traversal in @backstage/plugin-scaffolder-backend (CVE-2021-43783). Data can be tampered with by attackers. Mitigation: upgrade to 0.15.14 or later.
Original description
The description as published by the source.
Impact
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.
Patches
This vulnerability is fixed in version 0.15.14 of the @backstage/plugin-scaffolder-backend.
Workarounds
This attack is mitigated by restricting access and requiring reviews when registering or modifying scaffolder templates.
For more information
If you have any questions or comments about this advisory:
- Open an issue in the Backstage repository
- Visit our chat, linked to in Backstage README
Source: OSV.dev (Open Source Vulnerabilities) NVD GitHub Advisory OSV
Auto-generated summary
Assembled by SecPulse from the source data (CVSS, CWE, affected versions) using templates — no AI involved. Check the original description and references below for exact details.
A vulnerability tracked as CVE-2021-43783 has been found in @backstage/plugin-scaffolder-backend.
Data can be tampered with by attackers.
What to do: upgrade @backstage/plugin-scaffolder-backend to 0.15.14 or later.
If unsure, ask your IT team or search "@backstage/plugin-scaffolder-backend CVE-2021-43783" on the vendor's site.
CVE-2021-43783 (@backstage/plugin-scaffolder-backend) — CWE-22
Attack vector: remote (network-reachable) / no user interaction
Patched: 0.15.14 — apply immediately
Workaround: This attack is mitigated by restricting access and requiring reviews when registering or modifying scaffolder templates.
Plan: 1) Audit SBOM/dependencies, 2) Stage→prod upgrade, 3) Add WAF/proxy monitoring on affected endpoints, 4) Hunt IOCs in logs.
Refs: see the GHSA / vendor advisory / patched release linked on this page.
Path traversal (CWE-22) exists in @backstage/plugin-scaffolder-backend.
Check the vendor advisory for the affected versions of @backstage/plugin-scaffolder-backend.
Severity: ?. Data can be tampered with by attackers.
Update to 0.15.14.
Workaround: This attack is mitigated by restricting access and requiring reviews when registering or modifying scaffolder templates.
Search webserver/proxy logs for unusual request patterns matching this CVE's known IOCs. Run grep -r '@backstage/plugin-scaffolder-backend' . against your dependency files (package-lock.json, requirements.txt, go.sum) to find affected services.
Response actions
Concrete steps and command examples for SOC/SRE teams to execute in order
-
1Identify exposure identify
grep -r '@backstage/plugin-scaffolder-backend' . | grep -v node_modulesリポジトリと本番環境の依存ファイル (package-lock.json / requirements.txt / go.sum / Gemfile.lock 等) で
@backstage/plugin-scaffolder-backendを grep し、稼働しているサービス・バージョンを把握する。 -
2Apply temporary workaround mitigate
This attack is mitigated by restricting access and requiring reviews when registering or modifying scaffolder templates.パッチが適用されるまでの応急処置として、This attack is mitigated by restricting access and requiring reviews when registering or modifying scaffolder templates. を実施。回避策の副作用 (機能低下) を確認した上で。
-
3Apply patch patch
Upgrade @backstage/plugin-scaffolder-backend to 0.15.14ステージング環境で 0.15.14 に上げて回帰テスト → 本番反映。回帰テストはアプリの主要ハッピーパスを含めること。
-
4Post-deployment verification verify
Confirm patched version is live in productionパッチ適用後、ステージングで PoC または同等の悪用パターンを再現して脆弱性が閉じたことを確認。本番ではアクセスログ・WAF でアラート再発が無いか継続監視。
Affected packages
References
- advisory nvd.nist.gov
- package github.com
- web github.com
- web github.com