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TI-2018-02757 Aliases CVE-2018-3761GHSA-frc3-rhfw-jxf5

Improper authentication in Nextcloud Server

Priority LOW 39CWE-287Published · Updated

Key facts

Attack vector
Network
Privileges required
None
User interaction
Required
Attack complexity
Low
Impact type
Security bypass
Confidentiality · integrity · availability
High · High · None
Fix status
No fix listed

Attack profile from CVSS 3.1 · NVD. Fix status from CNA. Impact type from CWE-287.

Summary

Nextcloud Server before 12.0.8 and 13.0.3 suffer from improper authentication on the OAuth2 token endpoint. Missing checks potentially allowed handing out new tokens in case the OAuth2 client was partly compromised.

Why it matters now

EPSS 0.01657 76th percentileScored 2026-11-07
Fix No fix listed No fixed version in the sources yet

SSVC decision points

Not available: CISA has not published SSVC decision points for this record.

Affected products

VendorProductAffected versionsFixed inStatusSource
nextcloudNextcloud Server<13.0.3, <12.0.8—No fix listedCNA
  • Nextcloud Server Vendornextcloud Affected <13.0.3, <12.0.8 Fixed in — No fix listed CNA

CPE configurations NVD · 1

CPEVersionsRoleVendor
cpe:2.3:a:nextcloud:nextcloud_server:*:*:*:*:*:*:*:*before 12.0.8; 13.0.0 to before 13.0.3Vulnerablenextcloud
  • cpe:2.3:a:nextcloud:nextcloud_server:*:*:*:*:*:*:*:* Versions before 12.0.8; 13.0.0 to before 13.0.3 Vulnerable ·nextcloud

Remediation

No fixed version listed by the sources yet.

Vendor assessments

Red Hat

Red Hat's page for this CVE →

Not affected: 1 product
  • Red Hat

Timeline

  1. 2026-10-02 Threatist record created from CVE-2018-3761
  2. 2026-10-03 Alias added: GHSA-frc3-rhfw-jxf5

References

Advisory 2

  • TI-2023-20855 Users can delete external storage mount points CVSS 3.1HIGH 7.7
  • TI-2023-11091 Nextcloud download permissions can be changed by resharer CVSS 3.1HIGH 7.5
  • TI-2023-10624 Nextcloud Server vulnerable to SSRF via filter bypass due to lax checking on IPs CVSS 3.1MEDIUM 5.3
  • TI-2025-37238 Cross-site scripting in Nextcloud CVSS 3.1MEDIUM 6.4
  • TI-2023-11086 nextcloud vulnerable to Uncontrolled Resource Consumption CVSS 3.1MEDIUM 6.5
  • TI-2022-18738 Exception logging in Sharepoint app reveals clear-text connection details CVSS 3.1MEDIUM 6.5
See all 188 →

Sources

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