CVE-2026-58271

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Source
https://cve.org/CVERecord?id=CVE-2026-58271
Import Source
https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-58271.json
JSON Data
https://api.osv.dev/v1/vulns/CVE-2026-58271
Aliases
Published
2026-09-21T19:50:14Z
Modified
2026-09-22T11:45:43Z
Severity
  • 6.8 (Medium) CVSS_V3 - CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:N CVSS Calculator
Summary
@sync-in/server vulnerable to TOTP Brute-Force via `POST /api/app/sync/register`
Details

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.

Database specific 
{
    "cna_assigner":  "GitHub_M",
    "cwe_ids":  [
        "CWE-307"
    ],
    "osv_generated_from":  "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/58xxx/CVE-2026-58271.json"
}
References

Affected packages

Git / github.com/sync-in/server

Affected ranges

Type
GIT
Repo
https://github.com/sync-in/server
Events
Introduced
0 Unknown introduced commit / All previous commits are affected
Fixed
814d4e1f744fe709bdb4f5e9d4c6c6bd54982e09
Database specific
Show details 
{
    "extracted_events":  [
        {
            "introduced":  "0"
        },
        {
            "fixed":  "2.4.0"
        }
    ],
    "source":  "AFFECTED_FIELD"
}

Affected versions

v1.*
v1.1.0
v1.1.1
v1.10.0
v1.10.1
v1.11.0
v1.2.0
v1.2.1
v1.2.2
v1.3.0
v1.3.1
v1.3.2
v1.3.3
v1.3.4
v1.3.5
v1.3.6
v1.3.7
v1.3.8
v1.3.9
v1.4.0
v1.5.0
v1.5.1
v1.5.2
v1.6.0
v1.6.1
v1.7.0
v1.8.0
v1.8.1
v1.9.0
v1.9.1
v1.9.2
v1.9.3
v1.9.4
v1.9.5
v1.9.6
v2.*
v2.0.0
v2.1.0
v2.2.0
v2.2.1
v2.3.0

Database specific

source 
"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-58271.json"