CVE-2026-106559 is a medium-severity (CVSS 6.3) Path Traversal vulnerability in @backstage/plugin-scaffolder-backend-module-confluence-to-markdown. A fix is available for @backstage/plugin-scaffolder-backend-module-confluence-to-markdown — see the affected versions and patch details below.
Backstage: Improper input validation in Confluence to Markdown scaffolder module
Exploitation Status
No confirmed exploitation observed yet
- CISA’s own triage has not observed active exploitation or public proof-of-concept code for this CVE as of its last assessment.
Exploitation and automatability from CISA’s SSVC triage for CVE-2026-106559.
EPSS Exploitation Probability
Probability of exploitation in the next 30 days, from FIRST.org EPSS.
How urgent is this, really
CVE-2026-106559 by exploitation likelihood (EPSS) against impact (CVSS). Outside the shaded patch-first corner.
Where this sits among everything scored
Of 395,249 CVEs with a current EPSS score, this one falls in the < 10% band (highlighted). Counts from FIRST.org, log-scaled.
Real-World Exposure
How broadly this vulnerability is actually deployed: weekly install volume shows current usage, a proxy for how much of the ecosystem is exposed.
@backstage/plugin-scaffolder-backend-module-confluence-to-markdownnpmDescription
Impact
Insufficient input validation in the Confluence to Markdown scaffolder module could allow an attacker to influence file write operations during template execution. Exploitation requires a Backstage user to run a template that processes attacker-influenced Confluence content.
Patches
Patched in @backstage/plugin-scaffolder-backend-module-confluence-to-markdown version 0.3.25
Workarounds
If unable to update immediately:
- Restrict Confluence edit access to trusted users.
- Review Confluence page content before running scaffolder templates against untrusted pages.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 📦npm | @backstage/plugin-scaffolder-backend-module-confluence-to-markdown | all versions | 0.3.25npm install @backstage/plugin-scaffolder-backend-module-confluence-to-markdown@0.3.25 |
Affected Products
backstagelinuxfoundationbackstage\/plugin-scaffolder-backend-module-confluence-to-markdownlinuxfoundationDetection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for @backstage/plugin-scaffolder-backend-module-confluence-to-markdown, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update @backstage/plugin-scaffolder-backend-module-confluence-to-markdown to 0.3.25 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2026-106559 is resolved across your whole dependency graph.
Workarounds
Resolve every user-supplied path to its canonical form and reject anything that escapes the intended directory, and run the component under an account that has no read or write access outside the directory it legitimately serves.
Frequently Asked Questions
Is CVE-2026-106559 in your dependencies?
Find it across npm, including transitive dependencies.