Auth bypass in Bubka 2fauth

CVE-2026-63437

2FAuth is a web app to manage Two-Factor Authentication (2FA) accounts and generate their security codes. Prior to 8.0.0, the recipients() method in app/Api/v1/Controllers/TwoFAccountShareController.php receives a caller-selected TwoFAccount through Laravel model binding but does not call the manageShares authorization policy before listing its recipients. When account sharing is enabled, an authenticated user can call GET /api/v1/twofaccounts/{victimId}/recipients for accounts owned by other users, enumerate registered user IDs and display names, test exact email addresses with filter[nameOrEmail], and inspect each account's sharing relationships. This issue is fixed in version 8.0.0.

Vulnerability class: IDOR (Insecure Direct Object Reference)

Published .

CVSS v3 metric

CVSS v3 base score 6.5 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N.

EPSS exploit prediction

EPSS: 0.004 (29.4th percentile), scored .

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 29th percentile — 29.4% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

The 30-day trend appears once there are two daily scores.

Affected products

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2026-63437?
CVE-2026-63437 is a medium-severity vulnerability in Bubka 2fauth, classified under Authorization Bypass Through User-Controlled Key. CVSS score: 6.5/10. Published 2026-11-06.
How severe is CVE-2026-63437?
Medium severity. CVSS v3 base score is 6.5 out of 10.