CVE-2026-43978
HighCVSS 8.1Exploitation Probability (EPSS)
Low risk12th percentile - higher than 12% of all known CVEs
Summary
In wger prior to version 2.6, a gym trainer can escalate their session to any higher-privileged account (gym manager, general manager) by chaining two calls to the trainer-login endpoint. After a legitimate switch to a low-privileged user, the session flag `trainer.identity` is set and bypasses permission checks on subsequent trainer-login calls.
Risk Assessment
The organization is at risk of unauthorized access to all member data, contract modifications, gym configuration management, and access to personal information of other trainers and managers, potentially leading to privacy breaches and system integrity issues.
Recommendation
Immediately upgrade wger to version 2.6 or later, which includes the fix for this vulnerability. Before upgrading, consider restricting access to the trainer-login endpoint to trusted users only.
Other vulnerabilities in wger
See all- CVE-2026-43948Critical
In wger prior to version 2.6, there is a vulnerability that allows a user with gym.manage_gym permissions to reset the password of any user with no gym assignment. By exploiting an object comparison error, an attacker can take over the victim's account, and the victim's original password is invalidated.
- CVE-2026-43977High
In wger versions prior to 2.6, an authenticated user can read another user's private workout notes, exercise history, and training statistics by calling the /logs/ and /stats/ actions on a routine they do not own. The vulnerability is due to incorrect permission checks in RoutineViewSet, which grants read access to any authenticated user when the routine has is_template=True.
Original NVD description (English source)
wger is a free, open-source workout and fitness manager. In versions prior to 2.6, a gym trainer can escalate their session to any higher-privileged account (gym manager, general manager) by chaining two calls to the trainer-login endpoint. Once a trainer performs a legitimate switch into a low-privileged user, the session flag trainer.identity is set and this flag alone bypasses the permission check on all subsequent trainer-login calls. This grants full gym administration capabilities including viewing all member data, modifying contracts, managing gym configuration, and accessing other trainers' and managers' personal information. This issue has been fixed in version 2.6.