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.
CVE-2026-58272
MEDIUMPre-NVD 5.35.3—Trending — 3 sources updated this weekElevated
EchelonGraph scoreMEDIUM confidence
This medium-severity CVE scores 5.3 under a secondary CVSS source (NVD's own analysis pending). EPSS exploit probability: 0.3%, top 75% of all CVEs by exploit prediction. GitHub Security Advisory data not yet ingested — confidence will rise once GHSA publishes (typical lag: hours to days for open-source ecosystem CVEs; never for infrastructure-only CVEs).
Triggered by: NVD CVSS baseline
Sources: epss, secondary
5.3EG
EchelonGraph verdictMonitorLow exploitation likelihood right now — keep watching.
- Lower severity and no public exploit yet
CISA-KEV: Not listedEPSS PROB: 0%CVSS: 5.3Exploit: Elevated riskExposed: 0
No vendor fix yet — apply a workaround or compensating control (WAF / firewall / segmentation) and watch for a patch.
- CVSS v3
- 5.3
- EG Score
- 5.3(medium)
- EG Risk
- 55(Attend)EG Risk 55/100SSVC: Attend
EG Risk is EchelonGraph's 0–100 priority score: it fuses intrinsic severity with real-world exploitation and automatability so you can rank equal-severity CVEs and fix the most dangerous first. Higher = act sooner. Distinct from the 0–10 EG Score (severity).
How it’s computedSeverity53% × 45%Exploitation40% × 40%Automatability100% × 15%Action: Remediate soon — notable exploitation risk. - EPSS PROB
- 0%
- EPSS %ILE
- 25%
- KEV
- Not listed
Published
September 21, 2026
Last Modified
September 23, 2026
Advisory Details (1)
Auto-updated Sep 21, 2026🔬 Proof of concept available. Patch available. Sources: github.
github Patch Available🟡 PoC Available
Username/Login Enumeration via Timing Side-Channel on POST /api/auth/login (incomplete fix of the prior timing-attack advisory) · Advisory · Sync-in/server · GitHub
https://github.com/Sync-in/server/security/advisories/GHSA-29hq-23m2-2j47Vendor Advisories for CVE-2026-58272(1)
These vendors published their own advisory mentioning this CVE — often with vendor-specific remediation steps + affected product lists not in NVD.
Affected Packages
(1 across 1 ecosystem)
npm(1)
| Package | Vulnerable range | Fixed in | Dependents |
|---|---|---|---|
| @sync-in/server | — | 2.4.1 | — |
Weakness Classification(1)
MITRE Common Weakness Enumeration — the root-cause categories this CVE belongs to.
Data Freshness Timeline
(refreshed 10× in last 7d / 10× in last 30d)
Each row is a source pipeline that fetched or updated this CVE on that date, with what changed. For example, "NVD update" means NVD published or revised its analysis for this CVE; "MITRE cvelistV5" means we ingested or refreshed it from the CNA feed. Most recent first.
- 2026-09-24 18:55 UTCEG score recompute
- 2026-09-24 14:04 UTCEPSS rescore
- 2026-09-23 20:24 UTCEG score recompute
- 2026-09-23 19:48 UTCEG score recompute
- 2026-09-23 19:07 UTCEG score recompute
- 2026-09-23 17:54 UTCEPSS rescore
- 2026-09-22 19:55 UTCEG score recompute
- 2026-09-21 21:22 UTCEG score recompute
- 2026-09-21 20:43 UTCEG score recompute
- 2026-09-21 20:42 UTCMITRE cvelistV5first tracked
Related CVEs(same product + same CWE)
Same product
6 shownnpm:@sync-in/server
Frequently asked(5)
What is CVE-2026-58272?
CVE-2026-58272 is a medium vulnerability published on September 21, 2026. 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…
When was CVE-2026-58272 disclosed?
CVE-2026-58272 was first published in the National Vulnerability Database on September 21, 2026, with the most recent update on September 23, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2026-58272 actively exploited?
CVE-2026-58272 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 0% probability of exploitation in the next 30 days, which ranks it in the top 75.1% of all scored CVEs.
What is the CVSS score of CVE-2026-58272?
CVE-2026-58272 has a CVSS v3 base score of 5.3 (NVD).
How do I remediate CVE-2026-58272?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2026-58272, EchelonGraph cross-links them in the Vendor Advisories panel below — those typically contain the canonical remediation steps, fixed version numbers, and any vendor-specific mitigations.
Dependency Blast Radius
See which npm, PyPI, Go, and Maven packages are affected by CVE-2026-58272
Is Your Infrastructure Affected by CVE-2026-58272?
EchelonGraph automatically scans your cloud infrastructure and maps CVE exposure using blast radius analysis.