CVE-2026-58269: Sync-In Server

High severity, CVSS 8.1. EPSS: 0.2% chance of exploitation in the next 30 days.

Sync-in Server is an open-source platform for file storage, sharing, collaboration, and syncing. Prior to version 2.4.0, `POST /api/auth/token` authenticates with username and password only, then calls `getTokens()`, which returns full access and refresh JWTs without checking whether the account has TOTP 2FA enabled. An attacker with stolen or phished credentials can bypass 2FA in a single request. The parallel login endpoint (`POST /api/auth/login`) correctly enforces 2FA by calling `setCookies(user, res, true)`, which gates on `user.twoFaEnabled`. Version 2.4.0 patches the issue.

Affected products

• Sync-In Server: before 2.4.0 (fixed in 2.4.0)

Published 2026-09-21. Last modified 2026-09-24.