# Broken object-level authorization (BOLA / IDOR)

An actor can access another owner’s protected object by supplying its identifier.

**Candidate CWE:** [CWE-639](https://cwe.mitre.org/data/definitions/639.html)

## Test hypothesis

Create private O1 as A and O2 as B. Replay the O1 request with B’s credentials, retaining method and body; confirm B’s own O2 request succeeds. Test known child/export identifiers separately.

## Evidence required

A’s unique marker is returned to B, or A independently observes B’s unauthorized change. Preserve object privacy, both identities, the exact changed header or identifier, and cleanup.

## Rule out false positives

A UUID appearing in a response, a public object, intentional sharing, or HTTP 200 without protected data is not BOLA.

## Playbook and command references

- [Object, function, and property authorization](https://bug-bounty-field-manual.kmahshooq.chatgpt.site/modules/authz-matrix.html) — Turn identities, tenants, objects, roles, and lifecycle transitions into a reproducible permission matrix.
- [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.

[Find the associated command snippets](https://bug-bounty-field-manual.kmahshooq.chatgpt.site/commands.html?q=Object%2C%20function%2C%20and%20property%20authorization)

## 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

- [PortSwigger access control](https://portswigger.net/web-security/access-control)

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