KEVWire

Security intelligence, with context.

Response snapshot Nov 6, 2026, 19:41 UTC

Back to the wire
Permalink
VulnerabilityCVE-2026-43977

wger Vulnerable to IDOR: Authenticated Users Can Read Any User's Private Workout Session Data via Template Routine API

Any authenticated user can read another user's private workout session notes, exercise history, and training statistics by calling the /logs/ and /stats/ actions on a routine they do not own.

Published Updated

At a glance

Exploited
Not known
Severity
7.5 High (CVSS 3.1)
Chance of exploitation
0.3% in the next 30 days
Sources
1 source

What to do

Consult the exact GitHub advisory for affected versions, mitigation, and patch availability.

Read GitHub-reviewed advisory GHSA-cj9g-27ph-4cgv (opens a new tab)

What happened

Summary

Any authenticated user can read another user's private workout session notes, exercise history, and training statistics by calling the /logs/ and /stats/ actions on a routine they do not own.

The RoutinePermission class grants read access to any authenticated user when a routine has is_template=True, regardless of ownership. The /logs/ and /stats/ API actions use the same permission check but return the routine owner's personal training data instead of the requesting user's data, creating an insecure direct object reference (IDOR).

An attacker with a free account can enumerate all public template routine IDs via GET /api/v2/routine/?is_template=true, then call GET /api/v2/routine/{id}/logs/ and GET /api/v2/routine/{id}/stats/ to access the owner's private health data including workout notes, weights, repetitions, and performance statistics.

Continue reading

Description

wger exposes a REST API endpoint that allows any authenticated user to retrieve the private workout session notes, exercise logs, and training statistics belonging to another user, as long as that user has at least one routine marked as a public template.

The vulnerability exists in RoutineViewSet (wger/manager/api/views.py). The view defines two custom actions /logs/ and /stats/ that are intended to return data for the requesting user's own training history within a routine. However, the underlying permission check (RoutinePermission.has_object_permission) grants read access to any authenticated user when the routine has is_template=True, regardless of ownership.

When the /logs/ or /stats/ actions are invoked against a routine the attacker does not own, they return the owner's private workout history, not the attacker's.

Root Cause

File: wger/manager/api/permissions.py, lines 30–41

def has_object_permission(self, request, view, obj):
 if obj.user == request.user:
 return True

 if obj.is_template: # ← any template is readable
 return request.method in permissions.SAFE_METHODS # by any authenticated user

 return False

File: wger/manager/api/views.py, lines 173–199

@action(detail=True, url_path='logs')
def logs(self, request, pk):
 out = LogDisplaySerializer(
 self.get_object().logs_display(), # ← returns OWNER's logs, not request.user's
 many=True,
 ).data
 return Response(out)

@action(detail=True, url_path='stats')
def stats(self, request, pk):
 out = LogStatsDataSerializer(
 self.get_object().calculate_log_statistics() # ← owner's statistics
 ).data
 return Response(out)

self.get_object() retrieves the routine belonging to the owner (e.g., user A). Since is_template=True passes the permission check for any authenticated user, the attacker's request reaches logs_display() and calculate_log_statistics(), which return the owner's workout history, not the attacker's.

The intended behavior is that templates are public workout *plans* (exercise structure, sets, reps), but the /logs/ and /stats/ actions expose the *owner's personal training history* logged against that plan.

Impact

An authenticated attacker can:

1. Enumerate all public template routines across all users: GET /api/v2/routine/?is_template=true&is_public=true

2. Read private workout session notes (freeform text entered by the victim after each workout session)

3. Read full workout history including exercise names, weights, repetitions, and dates

4. Read training statistics including volume, intensity, and set counts per muscle group and mesocycle

This data is health-related and personal. Under GDPR and similar regulations, unauthorized access to personal health data constitutes a data breach.

Scenario

There are two users in the system:

- alice : a regular wger user who has been using the platform for months. She created a routine called "My 5/3/1 Program" and marked it as a public template so others can copy her exercise structure. She logs all her workouts with personal notes after each session.

- bob : a second registered user who has never interacted with alice's account.

The attack:

Bob calls the routine listing endpoint to find all public templates. He gets back alice's routine ID. He then calls /api/v2/routine/{id}/logs/ an endpoint that should only show his own logs but instead receives alice's full workout history, including all her session notes ("Felt strong today, PR on squat"), weights, and performance data.

Bob does not need to know alice's username. He only needs her routine ID, which is a sequential integer discoverable by iterating ?is_template=true.

Step-by-step

1. Bob registers a free account on the wger instance and obtains a JWT access token via POST /api/v2/token.

2. Bob calls GET /api/v2/routine/?is_template=true&is_public=true this lists all public template routines from all users across the platform, including their IDs.

3. For each routine ID returned, Bob calls GET /api/v2/routine/{id}/logs/ this returns the routine owner's workout sessions, including freeform personal notes and all logged exercises with weights and reps.

4. Bob calls GET /api/v2/routine/{id}/stats/ to get aggregated statistics (total volume, intensity by muscle group, weekly progression) for the routine's owner.

No special permissions are needed. A fresh account (1-minute-old) can exploit this.

Python PoC

#!/usr/bin/env python3
"""
PoC: IDOR - Workout Session Data Exposure via Template Routine API
Affected: wger 

### Recommended Fix

The `/logs/` and `/stats/` actions must filter results to the **requesting user**, not the routine owner.

python

wger/manager/api/views.py

@action(detail=True, url_path='logs') def logs(self, request, pk): routine = self.get_object()

Only return logs for the requesting user, regardless of routine ownership

out = LogDisplaySerializer( routine.logs_display(user=request.user), many=True, ).data

Affected package ranges reported by GitHub: wger: <= 2.5

Scores and how they were measured

CVSS base severity

7.5

Version 3.1As of

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N

Measurement source (opens a new tab)

How bad it is if exploited. Not a prediction of exploitation or proof you are exposed.

EPSS probability

0.3%

Scored Percentile 21.6%

Model and measurement source (opens a new tab)

A model's estimate of exploitation in the next 30 days, not certainty or your own risk.

Related technology

Follow Python packages (PyPI): RSS feedAll its recordsAsk your AI assistant

Sources

  1. Primary source

    GitHub-reviewed advisory GHSA-cj9g-27ph-4cgv (opens a new tab)

    The public advisory supplies the description, affected package/version ranges, and any listed CVSS metric. GitHub review is not local review.

    Published Checked

  2. Primary source

    GitHub public advisory API page (opens a new tab)

    The API page supplied GHSA-cj9g-27ph-4cgv, its actual identifiers, source dates, and structured metrics.

    Published Date not suppliedChecked

  3. Primary source

    FIRST measured EPSS score (opens a new tab)

    Measured EPSS probability and percentile for CVE-2026-43977, scored 2026-11-06. This is a model estimate, not proof of exposure.

    Published Checked

Cite this record

For factual claims, cite the primary sources above; cite KEVWire for its compilation, dates, and classifications.

APA

KEVWire. (2026, November 6). wger Vulnerable to IDOR: Authenticated Users Can Read Any User's Private Workout Session Data via Template Routine API (CVE-2026-43977). https://kevwire.com/record/CVE-2026-43977

MLA

"wger Vulnerable to IDOR: Authenticated Users Can Read Any User's Private Workout Session Data via Template Routine API (CVE-2026-43977)." KEVWire, 6 Nov. 2026, kevwire.com/record/CVE-2026-43977.

Chicago

KEVWire. "wger Vulnerable to IDOR: Authenticated Users Can Read Any User's Private Workout Session Data via Template Routine API (CVE-2026-43977)." Last modified November 6, 2026. https://kevwire.com/record/CVE-2026-43977.

Evidence summary (plain text)

wger Vulnerable to IDOR: Authenticated Users Can Read Any User's Private Workout Session Data via Template Routine API (May 14, 2026).
Any authenticated user can read another user's private workout session notes, exercise history, and training statistics by calling the /logs/ and /stats/ actions on a routine they do not own.

The RoutinePermission class grants read access to any authenticated user when a routine has is_template=True, regardless of ownership. The /logs/ and /stats/ API actions use the same permission check but return the routine owner's personal training data instead of the requesting user's data, creating an insecure direct object reference (IDOR).
CVSS 7.5 (version 3.1; evidence as of Nov 6, 2026; https://github.com/advisories/GHSA-cj9g-27ph-4cgv).
EPSS 0.3% for the following 30 days, scored Nov 6, 2026 (https://api.first.org/data/v1/epss?cve=CVE-2026-43977&date=2026-11-06).
Sources:
GitHub-reviewed advisory GHSA-cj9g-27ph-4cgv: https://github.com/advisories/GHSA-cj9g-27ph-4cgv
GitHub public advisory API page: https://api.github.com/advisories?type=reviewed&per_page=100&sort=updated&direction=desc
FIRST measured EPSS score: https://api.first.org/data/v1/epss?cve=CVE-2026-43977&date=2026-11-06
Record ID: CVE-2026-43977.
Record origin: Ingested record.
AI evidence: Not assessed.
Known exploitation: Not assessed.
Zero-day status: Not assessed. KEV membership alone does not establish zero-day status.
About this data

This record was ingested from a data source. Retrieved: Nov 6, 2026, 19:36 UTC. Ingestion is not an independent editorial investigation.

A CISA KEV listing documents known exploitation, not necessarily a zero-day; absence from the catalog does not prove a vulnerability has never been exploited.

Technology tags indicate possible relevance, not verified exposure. Confirm the affected product, version, and configuration against your own inventory; KEVWire does not scan your systems.

A personal reading checklist on this device, not verified remediation.

Record JSON

Your account

Email alerts

Email alerts are coming as part of KEVWire Premium: join the waitlist. To follow your stack today, use its RSS feed, which honors your filters, or connect an AI agent through the API.

Suggest an improvement

Ideas, missing sources, corrections, and bugs are all welcome. No account needed. Suggestions are reviewed by a person before anything changes.

Record details

Record detail