CVE•Published 2026-10-06•Modified 2026-10-13•1 article on news•3 live references•NVD data

CVE-2026-106503Linuxfoundation · Backstage\/plugin-scaffolder-backend

Vulnerability data via NVD (ingested)

CVSS v3.1

8.1

HIGH

CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:N

EPSS percentile

Exploit Prediction Scoring System · top 73% of all CVEs

Weaknesses (CWE)

CWE-178Improper Handling of Case Sensitivity CWE-284Improper Access Control

Description

Backstage is an open framework for building developer portals. Prior to 3.3.1, 3.4.1, 4.0.3 and 4.1.0, the @backstage/plugin-scaffolder-backend package is affected by scaffolder action input authorization bypass. An authenticated user with access to affected Scaffolder templates could bypass configured action restrictions. Depending on integration credentials, this could grant unauthorized access to repositories and related source-control resources. This issue is fixed in versions 3.3.1, 3.4.1, 4.0.3 and 4.1.0.

Timeline

Published 2026-10-06

Modified 2026-10-13

External references

NVD MITRE VulnCheck

Search for exposed instances

Shodan + Censys queries derived from NVD's CPE data. The vuln tag catches assets Shodan has explicitly linked to this CVE; the product / banner fingerprints find exposed instances even when the vuln tag was never applied (which is common).

Shodan · vuln tag0 hosts

vuln:CVE-2026-106503

Hosts Shodan has explicitly fingerprinted as vulnerable.

Shodan · product

product:"Linuxfoundation Backstage\/plugin-scaffolder-backend"

All exposed Linuxfoundation Backstage\/plugin-scaffolder-backend instances — cross-reference with the CVE's affected-version range.

Shodan · banner/body mention

http.html:"Backstage\/plugin-scaffolder-backend"

HTTP body or banner mentions "Backstage\/plugin-scaffolder-backend" — catches deploys Shodan didn't identify as a product.

More intel sources (5)

Shodan report

vuln:CVE-2026-106503