Vulnerabilities in pkg:npm/@backstage/plugin-auth-node

PACKAGE
Advisory Identifier: GHSA-xm5q-p7w3-x6cp
Advisory Summary

CVE-2026-106460 is a MODERATE (CVSS 6.8) explicit negative email verification can vulnerability (CWE-287: Improper Authentication) affecting Backstage libraries in the npm ecosystem. The issue involves explicit negative email verification can be ignored during shared oauth profile normalization. Remediation is available by upgrading affected packages to version 0.6.15, 0.7.5.

1 Known Advisory Record(s)
Package Vulnerability Intelligence

pkg:npm/@backstage/plugin-auth-node

1 Known Advisory Record(s)

Vulnerability advisories affecting package pkg:npm/@backstage/plugin-auth-node. Select an advisory below to view technical details or fixes.

Advisory ID CVE / NVD Severity Summary
GHSA-xm5q-p7w3-x6cp CVE-2026-106460 MODERATE Backstage: Explicit negative email verification can be ignored during shared OAuth profile normalization

CVE-2026-106460 at a Glance

CVE Identifier CVE-2026-106460
GHSA Identifier GHSA-xm5q-p7w3-x6cp
Severity MODERATE
CVSS v3.1 Base Score 6.8
CWE Classification CWE-287: Improper Authentication
Affected Product Backstage
Package Ecosystem npm
Published Date
Last Updated

Security Impact

CVSS: 6.8

The security impact metrics below are parsed directly from the CVSS v3.1 vector string (CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:N).

Attack Vector Network (AV:N)
Attack Complexity High (AC:H)
Privileges Required Low (PR:L)
User Interaction None (UI:N)
Scope Unchanged (S:U)
Confidentiality High (C:H)
Integrity High (I:H)
Availability None (A:N)

How to Fix CVE-2026-106460

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.

@backstage/plugin-auth-node fixed: 0.6.15
npm install @backstage/plugin-auth-node@0.6.15
@backstage/plugin-auth-node fixed: 0.7.5
npm install @backstage/plugin-auth-node@0.7.5
Verify Direct and Transitive Dependencies

Run the following command in your project directory to verify that all resolved dependencies use the patched release:

npm ls @backstage/plugin-auth-node

How to Check if You Are Affected

To determine whether your Node.js application is affected by CVE-2026-106460, inspect your project dependencies using npm:

npm ls @backstage/plugin-auth-node

Analyze 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 0.6.15), your application is affected.

Note: The npm ls @backstage/plugin-auth-node 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-287: Improper Authentication, where when an actor claims to have a given identity, the product does not prove or insufficiently proves that the claim is correct. 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

### Impact Several Passport-based authentication providers use shared OAuth profile normalization from `@backstage/plugin-auth-node`. Affected versions may pass an email to email-based sign-in resolvers even when verification metadata supplied for that same address is explicitly negative. The ID-token-only fallback likewise did not consistently respect `email_verified: false`. Exploitation requires a deployment where an admitted identity-provider user can supply or change an email address without verification and Backstage uses that profile email to resolve catalog identities. In that configuration, the user may be able to assume another catalog identity and obtain its associated access and permissions. An absent `email_verified` claim is not by itself considered an affected condition. Some providers rely on authoritative organizational provisioning and intentionally omit the optional claim. Operators using email-based sign-in resolution must ensure that the configured provider restricts sign-in to the intended user population and supplies an authoritative email address, either through provider verification or trusted immutable provisioning. This advisory covers the shared Passport profile normalization path when the selected profile email itself carries `verified: false`, when a matching raw provider email carries `email_verified: false`, or when an email obtained only from an ID token carries `email_verified: false`. It does not apply verification metadata from a different address or from a separate ID token to an independently fetched provider-profile email. The generic OIDC provider follows a separate profile transform and is covered by [GHSA-826h-28h9-65hg](https://github.com/backstage/backstage/security/advisories/GHSA-826h-28h9-65hg). The two advisories are complementary; deployments using both affected paths should apply both package updates. VMware Cloud uses a separate custom token transformation and is not changed by this patch. ### Patches Fixed in `@backstage/plugin-auth-node` versions `0.6.15` and `0.7.5`. Users remaining on the `0.6.x` line should upgrade to at least `0.6.15`; users on `0.7.x` should upgrade to at least `0.7.5`. The patched packages were released with [Backstage v1.49.7](https://github.com/backstage/backstage/releases/tag/v1.49.7) and [Backstage v1.54.7](https://github.com/backstage/backstage/releases/tag/v1.54.7), respectively. The fix is also present on `master` in [commit 507e65a](https://github.com/backstage/backstage/commit/507e65ab9160aae6b602513dbfaebdd6be0ca8bb). ### Workarounds - Require the identity provider to verify user-controlled email addresses before allowing sign-in. - Ensure profile emails are immutable and provisioned from a trusted organizational source. - Use a sign-in resolver that does not depend on the profile email. - Use a custom profile transform that omits an email when matching provider metadata explicitly marks it as unverified.

CVE-2026-106460 Affected Backstage Versions

2 component(s)
Fixed Versions:
0.6.150.7.5
Product / Package Ecosystem Affected Versions Fixed Version
@backstage/plugin-auth-node
npm
≥ 0.3.0
< 0.6.15
0.6.15
@backstage/plugin-auth-node
npm
≥ 0.7.0
< 0.7.5
0.7.5

References

Frequently Asked Questions

What is CVE-2026-106460?
CVE-2026-106460 is a security vulnerability in Backstage involving Explicit negative email verification can be ignored during shared OAuth profile normalization under CWE-287: Improper Authentication.
Which Backstage versions are affected?
Affected versions include releases prior to 0.6.15, 0.7.5 across affected packages: @backstage/plugin-auth-node.
What version fixes CVE-2026-106460?
Upgrading to 0.6.15, 0.7.5 (or the latest patched release for your respective branch) resolves the vulnerability.
Is @backstage/plugin-auth-node affected?
Yes, @backstage/plugin-auth-node is affected in releases prior to 0.6.15, 0.7.5. Upgrade your dependency to 0.6.15, 0.7.5 or later.
What is the CVSS score of CVE-2026-106460?
CVE-2026-106460 has a CVSS v3.1 base score of 6.8 (MODERATE) with vector string CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:N.
What CWE is associated with CVE-2026-106460?
CVE-2026-106460 is classified under CWE-287: Improper Authentication (When an actor claims to have a given identity, the product does not prove or insufficiently proves that the claim is correct.).
How can I check npm dependencies for CVE-2026-106460?
Run the dependency tree command: 'npm ls @backstage/plugin-auth-node'. This command lists direct and transitive dependencies in your build configuration so you can verify if a vulnerable version is resolved.
Machine-readable OSV JSON OSV v1.5 Schema
Normalized schema output
{
  "schema_version" : "1.4.0",
  "id" : "GHSA-xm5q-p7w3-x6cp",
  "modified" : "2026-10-07T20:23:52Z",
  "published" : "2026-10-07T20:23:52Z",
  "aliases" : [ "CVE-2026-106460" ],
  "summary" : "Backstage: Explicit negative email verification can be ignored during shared OAuth profile normalization",
  "details" : "### Impact\n\nSeveral Passport-based authentication providers use shared OAuth profile normalization from `@backstage/plugin-auth-node`. Affected versions may pass an email to email-based sign-in resolvers even when verification metadata supplied for that same address is explicitly negative. The ID-token-only fallback likewise did not consistently respect `email_verified: false`.\n\nExploitation requires a deployment where an admitted identity-provider user can supply or change an email address without verification and Backstage uses that profile email to resolve catalog identities. In that configuration, the user may be able to assume another catalog identity and obtain its associated access and permissions.\n\nAn absent `email_verified` claim is not by itself considered an affected condition. Some providers rely on authoritative organizational provisioning and intentionally omit the optional claim. Operators using email-based sign-in resolution must ensure that the configured provider restricts sign-in to the intended user population and supplies an authoritative email address, either through provider verification or trusted immutable provisioning.\n\nThis advisory covers the shared Passport profile normalization path when the selected profile email itself carries `verified: false`, when a matching raw provider email carries `email_verified: false`, or when an email obtained only from an ID token carries `email_verified: false`. It does not apply verification metadata from a different address or from a separate ID token to an independently fetched provider-profile email.\n\nThe generic OIDC provider follows a separate profile transform and is covered by [GHSA-826h-28h9-65hg](https://github.com/backstage/backstage/security/advisories/GHSA-826h-28h9-65hg). The two advisories are complementary; deployments using both affected paths should apply both package updates. VMware Cloud uses a separate custom token transformation and is not changed by this patch.\n\n### Patches\n\nFixed in `@backstage/plugin-auth-node` versions `0.6.15` and `0.7.5`. Users remaining on the `0.6.x` line should upgrade to at least `0.6.15`; users on `0.7.x` should upgrade to at least `0.7.5`.\n\nThe patched packages were released with [Backstage v1.49.7](https://github.com/backstage/backstage/releases/tag/v1.49.7) and [Backstage v1.54.7](https://github.com/backstage/backstage/releases/tag/v1.54.7), respectively. The fix is also present on `master` in [commit 507e65a](https://github.com/backstage/backstage/commit/507e65ab9160aae6b602513dbfaebdd6be0ca8bb).\n\n### Workarounds\n\n- Require the identity provider to verify user-controlled email addresses before allowing sign-in.\n- Ensure profile emails are immutable and provisioned from a trusted organizational source.\n- Use a sign-in resolver that does not depend on the profile email.\n- Use a custom profile transform that omits an email when matching provider metadata explicitly marks it as unverified.",
  "severity" : [ {
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    },
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    "url" : "https://nvd.nist.gov/vuln/detail/CVE-2026-106460"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/backstage/backstage/commit/507e65ab9160aae6b602513dbfaebdd6be0ca8bb"
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    "url" : "https://github.com/backstage/backstage/commit/f0a43dacd1b501064da042b43eab9c1e06371d38"
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    "url" : "https://github.com/backstage/backstage/commit/fc5e30aba8ea7282ed3658c3b985cec71051cf9d"
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    "url" : "https://github.com/backstage/backstage"
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    "url" : "https://github.com/backstage/backstage/releases/tag/v1.49.7"
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    "type" : "WEB",
    "url" : "https://github.com/backstage/backstage/releases/tag/v1.54.7"
  } ],
  "database_specific" : {
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    "severity" : "MODERATE",
    "github_reviewed" : true,
    "github_reviewed_at" : "2026-10-07T20:23:52Z",
    "nvd_published_at" : "2026-10-06T21:17:16Z"
  }
}