# CVE-2026-43976: wger: cross-tenant admin notes/contracts leak via gym=None bypass (5 views)

> Trainers without gym assignment can bypass access controls to read private admin notes, contracts, and user data for any user on the instance.

- **Severity:** High 7.1 (`CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:L/A:N`)
- **Exploited in the wild:** Not known
- **Login needed:** Any signed-in user
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** No
- **Published:** 7 Oct 2026
- **Updated:** 7 Oct 2026
- **Also known as:** GHSA-c72h-82w6-rqfp, PYSEC-2026-4313

## What is CVE-2026-43976?

CVE-2026-43976 is a high-severity missing authorization vulnerability in wger-project wger, published on 7 Oct 2026. Any signed-in user can exploit it over the network, with no action from the victim.

### Official description

wger is a free, open-source workout and fitness manager. Prior to version 2.6, five gym management views in wger apply a flawed gym-scope guard (`gym_a != gym_b`) that silently passes when both operands are `None`. A trainer with `gym.gym_trainer` and `gym.add_adminusernote` permissions and no gym assignment (`gym=None`) can read private admin notes, uploaded documents, gym contracts, user configuration, and user permission data for **any other unaffiliated user** on the instance. The subsequent querysets filter only on the attacker-supplied `member_id` with no secondary gym-scoped validation, so all records are disclosed. Version 2.6 fixes the issue.

Weakness: CWE-863 (Incorrect Authorization)

## Which versions are affected by CVE-2026-43976?

3 open source packages ship an affected version, including wger.


| Package | Ecosystem | Affected | Fixed in |
| --- | --- | --- | --- |
| `wger` | PyPI | All versions to 2.1 | None |
| `wger` | PyPI | All versions to 2.1 | None |
| `wger` | PyPI | All versions to 2.1 | None |

## How do I fix CVE-2026-43976?

No fix has been published for CVE-2026-43976 yet. Limit exposure of the affected software until one is available.

## Is CVE-2026-43976 being exploited?

It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-43976 exists.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-43976 and fix it if it is affected.

What it is: CVE-2026-43976 is a high-severity missing authorization vulnerability in wger-project wger, published on 7 Oct 2026. Any signed-in user can exploit it over the network, with no action from the victim.
Exploitation: It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-43976 exists.

Affected packages and fixed versions:
- wger (PyPI): affected all versions up to 2.1; no fix listed
- wger (PyPI): affected all versions up to 2.1; no fix listed
- wger (PyPI): affected all versions up to 2.1; no fix listed

Task:
1. Search the dependency manifests and lockfiles (for example package.json, package-lock.json, requirements.txt, poetry.lock, uv.lock, pom.xml, build.gradle, go.mod, Cargo.lock, Gemfile.lock) and any Dockerfiles for the affected packages, including transitive dependencies.
2. If an affected version is in use, upgrade it to the fixed version for its release line with the project's package manager, so the lockfile is regenerated. Prefer the smallest upgrade that fixes it.
3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead.
4. Run the tests and summarise what changed and why.
5. If nothing in the project is affected, say so and change nothing.

Reference: https://insights.sbomify.com/CVE-2026-43976/ (Markdown: https://insights.sbomify.com/CVE-2026-43976/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-43976
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-43976
- OSV: https://osv.dev/vulnerability/CVE-2026-43976

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-43976/
Summaries are generated and may contain mistakes; the official description above is the record.