Open Redirect in Wger-Project Wger
CVE-2026-86256
wger before 2.6 (affected versions <= 2.5.0) contains an open redirect vulnerability in the trainer_login view (wger/core/views/user.py). After a trainer enters impersonation mode, the view redirects to the user-supplied 'next' GET parameter via HttpResponseRedirect() without validating it with url_has_allowed_host_and_scheme(). An attacker who delivers a crafted link to an authenticated trainer can redirect the trainer's browser to an attacker-controlled domain, enabling phishing and leaking the wger URL structure (including the impersonated user's user_pk) via the Referer header.
Vulnerability class: Open Redirect
CVSS v3 metric
CVSS v3 base score 5.4 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N.
Affected products
Weakness classification (CWE)
References
- disclosure@vulncheck.com (vendor-advisory)
- disclosure@vulncheck.com (third-party-advisory)
Frequently asked questions
- What is CVE-2026-86256?
- CVE-2026-86256 is a medium-severity vulnerability in Wger-Project Wger, classified under URL Redirection to Untrusted Site (Open Redirect). CVSS score: 5.4/10. Published 2026-09-06.
- How severe is CVE-2026-86256?
- Medium severity. CVSS v3 base score is 5.4 out of 10.