Disclosure summary
### 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
Source-specific records & product guidance
Sources retain their own attribution and scoring. Follow the original record to confirm affected versions, fixed releases, and configuration conditions.
GitHub Reviewed Security Advisories · GHSA-xm5q-p7w3-x6cp
Open original source · Updated Oct 07, 2026
Backstage: Explicit negative email verification can be ignored during shared OAuth profile normalization
Source severity: MEDIUM / 0
| Ecosystem | Package | Affected range | First patched |
|---|---|---|---|
| npm | @backstage/plugin-auth-node | >= 0.3.0, < 0.6.15 | 0.6.15 |
| npm | @backstage/plugin-auth-node | >= 0.7.0, < 0.7.5 | 0.7.5 |
Original records & references
- NIST NVD record
- CVE Program record
- github.com — Reviewed advisory
PUBLISHED 2026-10-07T16:23:52-04:00
MODIFIED 2026-10-07T16:23:53-04:00
INGESTED 2026-10-08T12:30:39-04:00