CVE-2026-58272

Sync-in Server has Username/Login Enumeration via Timing Side-Channel on POST /api/auth/login (incomplete fix of the prior timing-attack advisory)

Published Sep 21, 2026 CVSS 3.1 · 5.3 Medium EPSS < 1% KEV · Not listed
Description
Sync-in Server is an open-source platform for file storage, sharing, collaboration, and syncing. Versions prior to 2.4.1 contain an observable timing discrepancy in the login endpoint because authentication attempts for nonexistent accounts return without performing the bcrypt comparison used for existing accounts. An unauthenticated attacker can measure response times to enumerate valid usernames or email addresses, facilitating credential-stuffing, password-spraying, and phishing attacks. Version 2.4.1 contains a patch.

Remediation

No solution or workaround provided in the CVE record

Tracking

Sign in to view the affected projects.

Advisories

Source ID Title
Github GHSA Github GHSA GHSA-29hq-23m2-2j47 Sync-in Server has Username/Login Enumeration via Timing Side-Channel on POST /api/auth/login (incomplete fix of the prior timing-attack advisory)
History
Type Values Removed Values Added
Metrics ssvc

{'options': {'Automatable': 'yes', 'Exploitation': 'poc', 'Technical Impact': 'partial'}, 'version': '2.0.3'}

Type Values Removed Values Added
First Time appeared Sync-in
Sync-in server
Vendors & Products Sync-in
Sync-in server
Type Values Removed Values Added
Description Sync-in Server is an open-source platform for file storage, sharing, collaboration, and syncing. Versions prior to 2.4.1 contain an observable timing discrepancy in the login endpoint because authentication attempts for nonexistent accounts return without performing the bcrypt comparison used for existing accounts. An unauthenticated attacker can measure response times to enumerate valid usernames or email addresses, facilitating credential-stuffing, password-spraying, and phishing attacks. Version 2.4.1 contains a patch.
Title Sync-in Server has Username/Login Enumeration via Timing Side-Channel on POST /api/auth/login (incomplete fix of the prior timing-attack advisory)
Weaknesses CWE-208
References
Metrics cvssV3_1

{'score': 5.3, 'vector': 'CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N'}

Weaknesses

Sources

Status
PUBLISHED
Assigner
GitHub_M
Published
Updated
Sep 23, 2026, 7:42 PM
Reserved
Jun 29, 2026, 9:54 PM
Status
Deferred
Published
Sep 21, 2026, 9:17 PM
Modified
Sep 30, 2026, 5:32 PM