# Authentication or MFA state bypass

A session that has not completed required authentication can perform protected operations.

**Candidate CWE:** [CWE-287](https://cwe.mitre.org/data/definitions/287.html)

## Test hypothesis

Stop a controlled login before MFA or verification completion. Make one private profile request using its intermediate credential. Compare with a completed session and an anonymous request.

## Evidence required

Protected controlled data or an action is available without the required step. Record actual authentication state, route, credential source, and resulting identity.

## Rule out false positives

Issuing an intermediate token, showing a login shell, or allowing explicitly public profile data is not a bypass.

## Playbook and command references

- [Authentication, recovery, federation, and session lifecycle](https://bug-bounty-field-manual.kmahshooq.chatgpt.site/modules/identity-session.html) — Test registration, recovery, identity changes, invitations, SSO enforcement, and deprovisioning as one account state machine.
- [REST, GraphQL, gRPC, WebSocket, and SSE permission parity](https://bug-bounty-field-manual.kmahshooq.chatgpt.site/modules/api-protocols.html) — Carry the same permission invariant across protocols, nested fields, streams, and alternate API versions.
- [MFA and passkeys: enrollment, proof, replacement, and recovery](https://bug-bounty-field-manual.kmahshooq.chatgpt.site/modules/authenticator-lifecycle.html) — Follow each authenticator from account binding to removal, and validate WebAuthn assertions without mistaking client UI or counter behavior for a security guarantee.

[Find the associated command snippets](https://bug-bounty-field-manual.kmahshooq.chatgpt.site/commands.html?q=Authentication%2C%20recovery%2C%20federation%2C%20and%20session%20lifecycle)

## Referenced by these target playbooks

[Web & API](https://bug-bounty-field-manual.kmahshooq.chatgpt.site/web-api.html) · [OSS & self-hosted](https://bug-bounty-field-manual.kmahshooq.chatgpt.site/oss.html) · [Mobile](https://bug-bounty-field-manual.kmahshooq.chatgpt.site/mobile.html) · [Desktop & extensions](https://bug-bounty-field-manual.kmahshooq.chatgpt.site/desktop.html) · [Cloud & containers](https://bug-bounty-field-manual.kmahshooq.chatgpt.site/cloud.html) · [AI, agents & MCP](https://bug-bounty-field-manual.kmahshooq.chatgpt.site/ai.html)

## Report checklist

- [ ] Capture the affected version, configuration, identities, and object ownership.
- [ ] Preserve a valid baseline and a negative control.
- [ ] Reproduce the forbidden data access, action, or state change on controlled fixtures.
- [ ] Explain the intended security rule and why the observed behavior violates it.
- [ ] State prerequisites, uncertainty, cleanup, and the smallest demonstrated impact.

## Conditional ATT&CK mapping

No direct ATT&CK mapping selected. Record the weakness and demonstrated impact without forcing an adversary-behavior classification. See the [mapping guide](https://bug-bounty-field-manual.kmahshooq.chatgpt.site/attack.html).

## Primary references

- [OWASP authentication](https://cheatsheetseries.owasp.org/cheatsheets/Authentication_Cheat_Sheet.html)

[Back to the complete vulnerability catalog](https://bug-bounty-field-manual.kmahshooq.chatgpt.site/vulnerabilities.html)