Medium · CVSS 6.3CVE-2026-106559

Backstage: Improper input validation in Confluence to Markdown scaffolder moduleCVE-2026-106559

Answer in brief

CVE-2026-106559 records a Medium severity (CVSS 6.3) vulnerability in Backstage: Improper input validation in Confluence to Markdown scaffolder module. The current sources do not mark it as known exploited. The current feed maps backstage/backstage (generic), @backstage/plugin-scaffolder-backend-module-confluence-to-markdown (generic). Check affected ranges and fixed versions before updating.

Analysis pending evidence review

HOL Guard separates source facts from reviewed analysis. See the methodology.

Published Oct 7, 2026Updated Oct 7, 2026Source checked Oct 7, 2026First seen by HOL Oct 7, 2026Material review Oct 7, 2026

Upstream Advisory

Key facts

Risk: Medium · CVSS 6.3
Exploitation: Not marked as known exploited
Affected software: 2 mapped packages or products
Fix availability: Available

Why this deserves its current priority

CVSS is 6.3. The current sources do not mark it as known exploited. Treat this as a source-backed prioritization signal, not a statement about your environment.

Analysis status

Analysis pending evidence review

Factual feed record only; HOL analysis is not approved for indexing. Read the methodology.

Affected scope and exposure questions

The current feed maps backstage/backstage (generic), @backstage/plugin-scaffolder-backend-module-confluence-to-markdown (generic). Check affected ranges and fixed versions before updating.

Mapped affected packages and fixed versions
Package	Affected range	Fixed version
backstage/backstagegeneric	<1.54.6	1.54.6
@backstage/plugin-scaffolder-backend-module-confluence-to-markdowngeneric	<0.3.25	0.3.25

Recommended response

Check inventory. Check lockfiles and deployed manifests for backstage/backstage, @backstage/plugin-scaffolder-backend-module-confluence-to-markdown.
Review the reported fix. Update backstage/backstage to 1.54.6; @backstage/plugin-scaffolder-backend-module-confluence-to-markdown to 0.3.25 if you use the affected versions. Test the change in a non-production environment first.

Evidence timeline and material changes

Published upstream
Oct 7, 2026
Evidence: source:cvelist:source_dates:source-dates:record
Source modified
Oct 7, 2026
Evidence: source:cvelist:source_dates:source-dates:record
First seen by HOL
Oct 7, 2026

Sources and claim methodology

Upstream source description

Backstage is an open framework for building developer portals. Prior to 0.3.25, the @backstage/plugin-scaffolder-backend-module-confluence-to-markdown package is affected by improper input validation in confluence to markdown scaffolder module. 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. This issue is fixed in version 0.3.25.

Quoted source text, attributed separately from HOL analysis.