Vulnerability in Sync-In Server
CVE-2026-58269
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.
CVSS v3 metric
CVSS v3 base score 8.1 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:N.
Affected products
- Sync-in Server — versions < 2.4.0
Weakness classification (CWE)
References
- security-advisories@github.com (x_refsource_CONFIRM)
Frequently asked questions
- What is CVE-2026-58269?
- CVE-2026-58269 is a high-severity vulnerability in Sync-In Server, classified under Authentication Bypass Using an Alternate Path or Channel. CVSS score: 8.1/10. Published 2026-09-21.
- How severe is CVE-2026-58269?
- High severity. CVSS v3 base score is 8.1 out of 10.