vulnerability / NVI-00015085 / Revision 1
Authorizer: Zero-click account takeover via OAuth identity linking to unverified email accounts
GitHub lists this reviewed advisory for github.com/authorizerdev/authorizer. Published version ranges and source prerequisites are shown below; this is not an inspection of a visitor’s application.
This report has not inspected your inventory, configuration, deployed build, reachability or evidence. A catalog listing and a severity score do not establish exposure or compromise.
01 / Meaning
Why it matters
Published affected context helps an owner decide what evidence to gather. This report has not examined your application.
02 / Applicability
The affected context
Affected versions, configuration prerequisites and known exclusions are public. Confirm each one against the deployed service.
github.com/authorizerdev/authorizer
source listed< 0.0.0-20260807033110-66fe488fd2a4
The OAuth callback handler links incoming OAuth identities (Google, GitHub, etc.) to existing accounts matched by email address without verifying that the existing account's email was verified by its original owner. An attacker who pre-registers with a victim's email address (without verifying it) gains persistent password-based access to the victim's account after the victim completes a normal OAuth login. Verified against HEAD (commit 73679fa). ## Root Cause In `internal/http_handlers/oauth_callback.go`, when an OAuth login occurs for an email that already exists in the database: Line 125: The existing user is looked up by email: existingUser, err := h.StorageProvider.GetUserByEmail(ctx, refs.StringValue(user.Email)) Line 164: The OAuth user object is replaced with the existing user: user = existingUser Lines 173-176: The OAuth provider is appended to the existing user's signup methods: signupMethod := existingUser.SignupMethods if !strings.Contains(signupMethod, provider) { signupMethod = signupMethod + "," + provider } user.SignupMethods = signupMethod Lines 179-181: If the existing account's email was NOT verified, it is automatically v
03 / Response
What to do next
- investigate
Identify the exact component and deployed version, examine the linked publisher’s conditions, and retain evidence of any mitigation.
Confirm current vendor support, compatibility and deployment evidence. This report has not tested a fix in your system. GitHub Advisory Database
A fixed release is not deployment evidence.
Check current vendor support and compatibility. After making a change, verify the deployed build and relevant runtime conditions. Keep the evidence, owner and time. An updated lockfile alone does not prove what is running.
04 / Limits
What this report cannot establish
- Customer inventory, deployment, reachability and exploitation have not been inspected.
05 / Provenance
Sources you can inspect
Each assertion retains its source. Mirrored records may repeat one underlying publisher; additional links are not independent corroboration.
- GHSA-29rf-f4vv-pvq6 ↗
GitHub Advisory Database · vendor advisory
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Public revision history
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- Revision 1 ·
First indexed by Null; source disclosure date is shown separately.