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TI-2026-29787 Aliases CVE-2026-41161GHSA-43fj-qp3h-hrh5

Username Enumeration via Timing Attack

Priority HIGH 70CWE-208Published · Updated

Key facts

Attack vector
Network
Privileges required
None
User interaction
None
Attack complexity
Low
Attack requirements
None
Impact type
Information disclosure
Confidentiality · integrity · availability
Low · None · None
Fix status
Fixed

Attack profile from CVSS 4.0 · CNA. Fix status from CNA and GitHub. Impact type from CWE-208.

Summary

Sync-in Server is a secure, open-source platform for file storage, sharing, collaboration, and syncing. Prior to version 2.2.0, the /api/auth/login endpoint contains a logic flaw that allows unauthenticated remote attackers to enumerate valid usernames by measuring the application's response time. This issue has been patched in version 2.2.0.

Why it matters now

Exploitation Proof of concept CISA SSVC · not in CISA KEV
EPSS 0.00333 26th percentileScored 2026-11-07
Fix Fixed server (Sync-in): 2.2.0@sync-in/server (npm): 2.2.0

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
Poc
Automatable
Yes
Technical impact
Partial

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

VendorProductAffected versionsFixed inStatusSource
Sync-inserverbefore 2.2.02.2.0Patch availableCNA
—@sync-in/server (npm)before 2.2.02.2.0Patch availableGHSA-43fj-qp3h-hrh5
  • server VendorSync-in Affected before 2.2.0 Fixed in 2.2.0 Patch available CNA
  • @sync-in/server (npm) Vendor— Affected before 2.2.0 Fixed in 2.2.0 Patch available GHSA-43fj-qp3h-hrh5

CPE configurations NVD · 1

CPEVersionsRoleVendor
cpe:2.3:a:sync-in:sync-in_server:*:*:*:*:*:*:*:*before 2.2.0VulnerableSync-in
  • cpe:2.3:a:sync-in:sync-in_server:*:*:*:*:*:*:*:* Versions before 2.2.0 Vulnerable ·Sync-in

Remediation

  • Fix · CNA server (Sync-in) Fixed in 2.2.0
  • Fix · GHSA-43fj-qp3h-hrh5 @sync-in/server (npm) Fixed in 2.2.0 Advisory →

Timeline

  1. 2026-10-02 Threatist record created from CVE-2026-41161
  2. 2026-10-03 Alias added: GHSA-43fj-qp3h-hrh5

References

Patch 1

Advisory 2

Other 1

  • TI-2025-41214 A Stored Cross-Site Scripting (XSS) vulnerability in Sync-in Server before 1.9.3 allows… CVSS 3.1MEDIUM 6.1
  • TI-2025-35423 Directory traversal vulnerability in Sync In server thru 1.1.1 allowing authenticated… CVSS 3.1MEDIUM 5.3

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences