CVE-2026-41161: sync-in server — Fix

Description

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.

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CVSS v3.1 Score

5.3

MEDIUM

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N

EPSS — Exploit Prediction

0.0005

Probability of exploitation

0.14%

Percentile rank

EPSS estimates the probability that this vulnerability will be exploited in the wild within the next 30 days. A higher score means more likely to be exploited.

Weakness Type (CWE)

CWE-208 CWE-208

Affected Products

Vendor	Product	Versions
sync-in	sync-in_server	< 2.2.0

References

Advisories & Patches

https://github.com/Sync-in/server/releases/tag/v2.2.0 https://github.com/Sync-in/server/security/advisories/GHSA-43fj-qp3h-hrh5 https://github.com/Sync-in/server/security/advisories/GHSA-43fj-qp3h-hrh5

Frequently Asked Questions

What is CVE-2026-41161? +

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. It has a CVSS v3.1 base score of 5.3 (MEDIUM).

How severe is CVE-2026-41161? +

CVE-2026-41161 has a CVSS v3.1 score of 5.3 out of 10, rated MEDIUM. This is a medium-severity vulnerability that should be remediated as part of regular maintenance. The EPSS score is 0.0005, placing it in the 0th percentile for exploitation probability.

What products are affected by CVE-2026-41161? +

CVE-2026-41161 affects products from sync-in, specifically: sync-in_server. Check the affected products table above for specific version ranges.

How do I check if I'm vulnerable to CVE-2026-41161? +

You can use Secably's free Website Scanner to check your website for known vulnerabilities. For infrastructure scanning, use the Port Scanner to identify exposed services that may be affected. Check the vendor advisories linked above for specific patch and version information.

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