django-access-review

What the source does

• FilesystemNone observedNo reads or writes in the source
• NetworkNone observedNo outbound calls in the source
• ShellNone observedNo commands run in the source
• DependenciesPinnedNothing floats
• SecretsNone foundNo keys in source

Five audit layers

Gates applied: no behavioural pass.

.agents/skills

CLAUDE.md

Audit 0.4.1 · source sha 7bf25505c14b · 28 Oct 2026Report an issue or request a re-scan

• Publishergetsentry GitHub organizationOwner of the repository this skill is read from
• Source foldergetsentry/skills/skills/django-access-reviewThe exact folder we audited
• LicenceApache-2.0As the repository states it
• Commit pinned for this verdict7bf25505c14bA new audit runs when the source changes
• Repository statusNot archivedLast push 1 day ago
• Sandboxed runNot runSkills are read, not executed; layer L4 is skipped

Its description: Django access control and IDOR security review. Use when reviewing Django views, DRF viewsets, ORM queries, or any Python/Django code handling user authorization. Trigger keywords: "IDOR", "access control",…

---
name: django-access-review
description: 'Django access control and IDOR security review. Use when reviewing Django views, DRF viewsets, ORM queries, or any Python/Django code handling user authorization. Trigger keywords: "IDOR", "access control", "authorization", "Django permissions", "object permissions", "tenant isolation", "broken access".'
allowed-tools: Read Grep Glob Bash Task
license: LICENSE
---

<!--
Reference material based on OWASP Cheat Sheet Series (CC BY-SA 4.0)
https://cheatsheetseries.owasp.org/
-->

# Django Access Control & IDOR Review

Find access control vulnerabilities by investigating how the codebase answers one question:

**Can User A access, modify, or delete User B's data?**

## Philosophy: Investigation Over Pattern Matching

Do NOT scan for predefined vulnerable patterns. Instead:

1. **Understand** how authorization works in THIS codebase
2. **Ask questions** about specific data flows
3. **Trace code** to find where (or if) access checks happen
4. **Report** only what you've confirmed through investigation

Every codebase implements authorization differently. Your job is to understand this specific implementation, then find gaps.

---

## Phase 1: Understand the Authorization Model

Before looking for bugs, answer these questions about the codebase:

### How is authorization enforced?

Research the codebase to find:

```
□ Where are permission checks implemented?
  - Decorators? (@login_required, @permission_required, custom?)
  - Middleware? (TenantMiddleware, AuthorizationMiddleware?)
  - Base classes? (BaseAPIView, TenantScopedViewSet?)
  - Permission classes? (DRF permission_classes?)
  - Custom mixins? (OwnershipMixin, TenantMixin?)

□ How are queries scoped?
  - Custom managers? (TenantManager, UserScopedManager?)
  - get_queryset() overrides?
  - Middleware that sets query context?

□ What's the ownership model?
  - Single user ownership? (document.owner_id)
  - Organization/tenant ownership? (document.organization_id)
  - Hierarchical? (org -> team -> user -> resource)
  - Role-based within context? (org admin vs member)
```

### Investigation commands

```bash
# Find how auth is typically done
grep -rn "permission_classes\|@login_required\|@permission_required" --include="*.py" | head -20

# Find base classes that views inherit from
grep -rn "class Base.*View\|class.*Mixin.*:" --include="*.py" | head -20

# Find custom managers
grep -rn "class.*Manager\|def get_queryset" --include="*.py" | head -20

# Find ownership fields on models
grep -rn "owner\|user_id\|organization\|tenant" --include="models.py" | head -30
```

**Do not proceed until you understand the authorization model.**

---

## Phase 2: Map the Attack Surface

Identify endpoints that handle user-specific data:

### What resources exist?

```
□ What models contain user data?
□ Which have ownership fields (owner_id, user_id, organization_id)?
□ Which are accessed via ID in URLs or request bodies?
```

### What operations are exposed?

For each resource, map:
- List endpoints - what data is returned?
- Detail/retrieve endpoints - how is the object fetched?
- Create endpoints - who sets the owner?
- Update endpoints - can users modify others' data?
- Delete endpoints - can users delete others' data?
- Custom actions - what do they access?

---

## Phase 3: Ask Questions and Investigate

For each endpoint that handles user data, ask:

### The Core Question

**"If I'm User A and I know the ID of User B's resource, can I access it?"**

Trace the code to answer this:

```
1. Where does the resource ID enter the system?
   - URL path: /api/documents/{id}/
   - Query param: ?document_id=123
   - Request body: {"document_id": 123}

2. Where is that ID used to fetch data?
   - Find the ORM query or database call

3. Between (1) and (2), what checks exist?
   - Is the query scoped to current user?
   - Is there an explicit ownership check?
   - Is there a permission check on the object?
   - Does a base class or mixin enforce access?

4. If you can't find a check, is there one you missed?
   - Check parent classes
   - Check middleware
   - Check managers
   - Check decorators at URL level
```

### Follow-Up Questions

```
□ For list endpoints: Does the query filter to user's data, or return everything?

□ For create endpoints: Who sets the owner - the server or the request?

□ For bulk operations: Are they scoped to user's data?

□ For related resources: If I can access a document, can I access its comments?
  What if the document belongs to someone else?

□ For tenant/org resources: Can User in Org A access Org B's data by changing
  the org_id in the URL?
```

---

## Phase 4: Trace Specific Flows

Pick a concrete endpoint and trace it completely.

### Example Investigation

```
Endpoint: GET /api/documents/{pk}/

1. Find the view handling this URL
   → DocumentViewSet.retrieve() in api/views.py

2. Check what DocumentViewSet inherits from
   → class DocumentViewSet(viewsets.ModelViewSet)
   → No custom base class with authorization

3. Check permission_classes
   → permission_classes = [IsAuthenticated]
   → Only checks login, not ownership

4. Check get_queryset()
   → def get_queryset(self):
   →     return Document.objects.all()
   → Returns ALL documents!

5. Check for has_object_permission()
   → Not implemented

6. Check retrieve() method
   → Uses default, which calls get_object()
   → get_object() uses get_queryset(), which returns all

7. Conclusion: IDOR - Any authenticated user can access any document
```

### What to look for when tracing

```
Potential gap indicators (investigate further, don't auto-flag):
- get_queryset() returns .all() or filters without user
- Direct Model.objects.get(pk=pk) without ownership in query
- ID comes from request body for sensitive operations
- Permission class checks auth but not ownership
- No has_object_permission() and queryset isn't scoped

Likely safe patterns (but verify the implementation):
- get_queryset() filters by request.user or user's

Excerpt, first 6,000 characters of SKILL.md, verbatim from the audited commit. It is text from someone else’s repository, quoted so you can judge it before your agent reads it.

git clone https://github.com/getsentry/skills
git -C skills checkout 7bf25505c14b

Works in

1. 2026-10-28
   ✓SAFE B 89 / 100

   first audit · source 7bf25505c14b

Questions about django-access-review

• github.com/getsentry/skills/tree/main/skills/django-access-revie — the audited source at commit 7bf25505c14b and every finding aboveObserved · 28 Oct 2026

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