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.
- Exploited in the wild
- Not known
- Login needed
- Any signed-in user
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- None listed
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
Which versions are affected by CVE-2026-43976?
3 open source packages ship an affected version, including wger.
| Package | 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.
Upgrade, and check permissions on every request on the server, not only in the interface. More about Missing authorization.
Is CVE-2026-43976 being exploited?
It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-43976 exists.
Sources
Also known as GHSA-c72h-82w6-rqfp, PYSEC-2026-4313.