Open-Source Security Intelligence

Know every vulnerability
before it knows you.

DevGuard continuously monitors your dependencies and alerts you when CVEs like this one affect your stack — with real-time threat intelligence built for developers.

Search

CVE-2026-58271

MediumCVSS 6.8 / 10
Published Sep 21, 2026·Last modified Sep 22, 2026
Affected Components(39)
sync-in/server
2.3.0
sync-in/server
1.9.1
sync-in/server
1.11.0
1 / 13
Description

Sync-in Server is an open-source platform for file storage, sharing, collaboration, and syncing. Prior to version 2.4.0, POST /api/app/sync/register accepts credentials and a TOTP code to register a desktop sync client. On a failed TOTP, SyncClientsManager.register() calls updateAccesses(user, ip, false), which hits a freeze branch that writes passwordAttempts back unchanged. The counter never reaches USER_MAX_PASSWORD_ATTEMPTS (10) and the lockout gate never fires. A successful guess returns a {clientId, clientToken} pair. The token can be exchanged via POST /api/app/sync/auth/cookie for a full JWT. While the code is valid, the attacker can also call POST /api/auth/2fa/disable to permanently remove MFA. Version 2.4.0 patches the issue.

Upload your SBOM

Upload your own SBOM in CycloneDX 1.6 or higher (JSON) directly here to check your vulnerabilities.

Risk Scores
Base Score
6.8

The vulnerability can be exploited over the network without needing physical access. It is difficult for an attacker to exploit this vulnerability and may require special conditions. An attacker needs basic access or low-level privileges. No user interaction is needed for the attacker to exploit this vulnerability. The impact is confined to the system where the vulnerability exists. There is a high impact on the confidentiality of the information. There is a high impact on the integrity of the data.

Threat Intelligence
6.2

Exploitation attempts have been detected. Elevated vigilance and prompt remediation are advised.

EPSS
0.22%

The exploit probability is very low. The vulnerability is unlikely to be exploited in the next 30 days.

Exploit
Not available

We did not find any exploit available. Neither in GitHub repositories nor in the Exploit-Database.

Scan your project

Continuously monitor your dependencies and get alerted when vulnerabilities like this one affect your stack.

Checkout DevGuard