CVE-2026-539584gaBoards: SSO Pre-Account Takeover / Hijacking via Mass Assignment

4gaBoards is a boards system for realtime project management. Prior to 3.3.9, 4gaBoards allows an authenticated user to modify ssoGoogleId, ssoGoogleEmail, ssoGithubId, ssoGithubUsername, ssoGithubEmail, ssoMicrosoftId, ssoMicrosoftEmail, ssoOidcId, and ssoOidcEmail through PATCH /api/users/:id. The whitelist in server/api/controllers/users/update.js mass assigns these backend-managed identity attributes from user input. An attacker can place a victim's provider identifier on an attacker-controlled account, causing the default lookup in helpers such as server/api/helpers/users/get-create-one-for-github-sso.js to match the victim's first SSO login to the attacker's account before the email-linkage flow runs. The victim is logged into the attacker-controlled account, and projects, boards, or data the victim creates remain accessible through the attacker's original local credentials. This issue is fixed in version 3.3.9.

CVSS

7.6 HIGH (v3.1, CNA)CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:H/I:H/A:L

Weakness (CWE)

CWE-287, CWE-915

Known exploited

Not in CISA's KEV catalog

EPSS (exploitation in the next 30 days)

Not loaded for this CVE

Assigned by

GitHub_M

NVD analysis

Deferred

Record last updated

Aug 19, 2026

First seen by InfoSec Signals

Oct 9, 2026

The CVE record on cve.org · NVD's entry

The CVE record is authoritative. Products marked “from the name” were identified from the CNA's free-text names, not a CPE, and are matched less certainly. This product uses the NVD API but is not endorsed or certified by the NVD.