Medium, CVSS 6.8npmAmendedPublished
Backstage: Explicit negative email verification can be ignored during shared OAuth profile normalization
CVE-2026-106460 · GHSA-xm5q-p7w3-x6cp
- Affected
- npm @backstage/plugin-auth-node >= 0.3.0, < 0.6.15; >= 0.7.0, < 0.7.5
- Fixed in
- 0.6.150.7.5· Vendor fix available
- Issue
- 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 emailverified: 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 emailverified 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…
Recommended action: Upgrade to 0.7.5 or 0.6.15 by release line, then redeploy and verify.A vendor fix does not resolve your finding until you verify it in your own systems.