CVE-2026-106501: Backstage Sensitive Information Exposure Vulnerability
CRITICALCVE-2026-106501 is a CRITICAL (CVSS 9.6) sensitive information exposure vulnerability (CWE-200: Exposure of Sensitive Information to an Unauthorized Actor) affecting Backstage libraries in the npm ecosystem. The issue involves sensitive information exposure in scaffolder. Remediation is available by upgrading affected packages to version 3.3.1, 3.4.1, 4.0.3, 4.1.0.
CVE-2026-106501 at a Glance
Security Impact
CVSS: 9.6
The security impact metrics below are parsed directly from the CVSS v3.1 vector string (CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:N).
How to Fix CVE-2026-106501
To remediate this vulnerability, upgrade all affected Backstage dependencies to a patched release. Both direct and transitive dependencies should be checked, as frameworks or security libraries may pull in vulnerable versions transitively.
npm install @backstage/plugin-scaffolder-backend@3.3.1npm install @backstage/plugin-scaffolder-backend@3.4.1npm install @backstage/plugin-scaffolder-backend@4.0.3npm install @backstage/plugin-scaffolder-backend@4.1.0Run the following command in your project directory to verify that all resolved dependencies use the patched release:
npm ls @backstage/plugin-scaffolder-backendHow to Check if You Are Affected
To determine whether your Node.js application is affected by CVE-2026-106501, inspect your project dependencies using npm:
npm ls @backstage/plugin-scaffolder-backendAnalyze the terminal output to locate any version of Backstage in your dependency tree. If any resolved version matches the vulnerable ranges listed in the table below (for example, versions earlier than 3.3.1), your application is affected.
Note: The npm ls @backstage/plugin-scaffolder-backend command inspects dependencies declared in your package.json and lockfile; it does not perform automated runtime dynamic scanning.
Technical Details
Vulnerability Mechanism & Technical Analysis
This vulnerability is classified under CWE-200: Exposure of Sensitive Information to an Unauthorized Actor, where the product exposes sensitive information to an actor that is not explicitly authorized to have access to that information. In Backstage, software state validation or input boundaries are circumvented during processing. Review the official source advisory statement below for specific affected components, classes, and reproduction details.
Source Advisory Statement
CVE-2026-106501 Affected Backstage Versions
4 component(s)| Product / Package | Ecosystem | Affected Versions | Fixed Version |
|---|---|---|---|
|
@backstage/plugin-scaffolder-backend
|
npm |
< 3.3.1
|
3.3.1
|
|
@backstage/plugin-scaffolder-backend
|
npm |
≥ 3.4.0
< 3.4.1
|
3.4.1
|
|
@backstage/plugin-scaffolder-backend
|
npm |
≥ 4.0.0
< 4.0.3
|
4.0.3
|
|
@backstage/plugin-scaffolder-backend
|
npm |
≥ 4.0.4
< 4.1.0
|
4.1.0
|
References
Frequently Asked Questions
What is CVE-2026-106501?
Which Backstage versions are affected?
What version fixes CVE-2026-106501?
Is @backstage/plugin-scaffolder-backend affected?
What is the CVSS score of CVE-2026-106501?
What CWE is associated with CVE-2026-106501?
How can I check npm dependencies for CVE-2026-106501?
Machine-readable OSV JSON
OSV v1.5 Schema
{
"schema_version" : "1.4.0",
"id" : "GHSA-g2v8-7jhw-pp8p",
"modified" : "2026-10-07T17:59:19Z",
"published" : "2026-10-07T17:59:19Z",
"aliases" : [ "CVE-2026-106501" ],
"summary" : "Backstage: Sensitive information exposure in Scaffolder",
"details" : "### Impact\n\nAn authenticated Backstage user who can read another user's Scaffolder task may receive internal execution data. In deployments where that data contains credentials for an external service, this may permit disclosure and unauthorized changes in that external service.\n\n### Patches\n\nPatched in `@backstage/plugin-scaffolder-backend` version `4.1.0`\n\n### Workarounds\n\n- Configure `scaffolder.task.read` with the `isTaskOwner` condition so users can only read tasks they created.\n- Restrict affected integrations and workflows to trusted operators until an upgrade is available.",
"severity" : [ {
"type" : "CVSS_V3",
"score" : "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:N"
} ],
"affected" : [ {
"package" : {
"ecosystem" : "npm",
"name" : "@backstage/plugin-scaffolder-backend"
},
"ranges" : [ {
"type" : "ECOSYSTEM",
"events" : [ {
"introduced" : "0"
}, {
"fixed" : "3.3.1"
} ]
} ]
}, {
"package" : {
"ecosystem" : "npm",
"name" : "@backstage/plugin-scaffolder-backend"
},
"ranges" : [ {
"type" : "ECOSYSTEM",
"events" : [ {
"introduced" : "3.4.0"
}, {
"fixed" : "3.4.1"
} ]
} ]
}, {
"package" : {
"ecosystem" : "npm",
"name" : "@backstage/plugin-scaffolder-backend"
},
"ranges" : [ {
"type" : "ECOSYSTEM",
"events" : [ {
"introduced" : "4.0.0"
}, {
"fixed" : "4.0.3"
} ]
} ]
}, {
"package" : {
"ecosystem" : "npm",
"name" : "@backstage/plugin-scaffolder-backend"
},
"ranges" : [ {
"type" : "ECOSYSTEM",
"events" : [ {
"introduced" : "4.0.4"
}, {
"fixed" : "4.1.0"
} ]
} ]
} ],
"references" : [ {
"type" : "WEB",
"url" : "https://github.com/backstage/backstage/security/advisories/GHSA-g2v8-7jhw-pp8p"
}, {
"type" : "ADVISORY",
"url" : "https://nvd.nist.gov/vuln/detail/CVE-2026-106501"
}, {
"type" : "WEB",
"url" : "https://github.com/backstage/backstage/commit/66d2219edf0abe33ab7d0c1ced5d069d1e065be5"
}, {
"type" : "WEB",
"url" : "https://github.com/backstage/backstage/commit/c19838870476a8e29144c84b1a5ac0654ec20fb5"
}, {
"type" : "WEB",
"url" : "https://github.com/backstage/backstage/commit/e262d649981ff99bb01ca7077807ae3e25e85560"
}, {
"type" : "PACKAGE",
"url" : "https://github.com/backstage/backstage"
}, {
"type" : "WEB",
"url" : "https://github.com/backstage/backstage/releases/tag/v1.49.6"
}, {
"type" : "WEB",
"url" : "https://github.com/backstage/backstage/releases/tag/v1.50.5"
}, {
"type" : "WEB",
"url" : "https://github.com/backstage/backstage/releases/tag/v1.54.6"
} ],
"database_specific" : {
"cwe_ids" : [ "CWE-200", "CWE-201" ],
"severity" : "CRITICAL",
"github_reviewed" : true,
"github_reviewed_at" : "2026-10-07T17:59:19Z",
"nvd_published_at" : "2026-10-06T22:17:05Z"
}
}