Auth bypass in Wger
CVE-2026-27838
wger is a free, open-source workout and fitness manager. Five routine detail action endpoints check a cache before calling `self.get_object()`. In versions up to and including 2.4, ache keys are scoped only by `pk` — no user ID is included. When a victim has previously accessed their routine via the API, an attacker can retrieve the cached response for the same PK without any ownership check. Commit e964328784e2ee2830a1991d69fadbce86ac9fbf contains a patch for the issue.
Vulnerability class: IDOR (Insecure Direct Object Reference)
EPSS: 0.002 (15.7th percentile) — read the EPSS interpretation.
CVSS v3 metric
CVSS v3 base score 3.1 (Low). Vector: CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:L/I:N/A:N.
Affected products
- Wger
- Wger-project Wger — versions <= 2.4
Weakness classification (CWE)
References
- security-advisories@github.com (x_refsource_CONFIRM, Exploit, Vendor Advisory)
- security-advisories@github.com (Patch, x_refsource_MISC)
Frequently asked questions
- What is CVE-2026-27838?
- CVE-2026-27838 is a low-severity vulnerability in Wger, classified under Authorization Bypass Through User-Controlled Key. CVSS score: 3.1/10. Published 2026-02-26.
- How severe is CVE-2026-27838?
- Low severity. CVSS v3 base score is 3.1 out of 10.