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TI-2023-27199 Aliases CVE-2023-49792

Bruteforce protection can be bypassed with misconfigured proxy

Priority MEDIUM 50CWE-307Published · Updated

Key facts

Attack vector
Network
Privileges required
None
User interaction
None
Attack complexity
Low
Impact type
Security bypass
Confidentiality · integrity · availability
High · High · High
Fix status
Fixed

Attack profile from CVSS 3.1 · NVD. Fix status from CNA. Impact type from CWE-307.

Summary

Nextcloud Server provides data storage for Nextcloud, an open source cloud platform. In Nextcloud Server prior to versions 26.0.9 and 27.1.4; as well as Nextcloud Enterprise Server prior to versions 23.0.12.13, 24.0.12.9, 25.0.13.4, 26.0.9, and 27.1.4; when a (reverse) proxy is configured as trusted proxy the server could be tricked into reading a wrong remote address for an attacker, allowing them executing authentication attempts than intended. Nextcloud Server versions 26.0.9 and 27.1.4 and Nextcloud Enterprise Server versions 23.0.12.13, 24.0.12.9, 25.0.13.4, 26.0.9, and 27.1.4 contain a patch for this issue. No known workarounds are available.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.01041 64th percentileScored 2026-11-07
Fix Fixed security-advisories (nextcloud): 23.0.12.13, 24.0.12.9, 25.0.13.4 +2

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
None
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
nextcloudsecurity-advisories23.0.0 to before 23.0.12.13; 24.0.0 to before 24.0.12.9; 25.0.0 to before 25.0.13.4; 26.0.0 to before 26.0.9; 27.0.0 to before 27.1.423.0.12.13, 24.0.12.9, 25.0.13.4, 26.0.9, 27.1.4Patch availableCNA
  • security-advisories Vendornextcloud Affected 23.0.0 to before 23.0.12.13; 24.0.0 to before 24.0.12.9; 25.0.0 to before 25.0.13.4; 26.0.0 to before 26.0.9; 27.0.0 to before 27.1.4 Fixed in 23.0.12.13, 24.0.12.9, 25.0.13.4, 26.0.9, 27.1.4 Patch available CNA

CPE configurations NVD · 5

CPEVersionsRoleVendor
cpe:2.3:a:nextcloud:nextcloud_server:*:*:*:*:enterprise:*:*:*23.0.0 to before 23.0.12.13; 24.0.0 to before 24.0.12.9; 25.0.0 to before 25.0.13.4Vulnerablenextcloud
cpe:2.3:a:nextcloud:nextcloud_server:*:*:*:*:-:*:*:*26.0.0 to before 26.0.9Vulnerablenextcloud
cpe:2.3:a:nextcloud:nextcloud_server:*:*:*:*:enterprise:*:*:*26.0.0 to before 26.0.9Vulnerablenextcloud
cpe:2.3:a:nextcloud:nextcloud_server:*:*:*:*:-:*:*:*27.0.0 to before 27.1.4Vulnerablenextcloud
cpe:2.3:a:nextcloud:nextcloud_server:*:*:*:*:enterprise:*:*:*27.0.0 to before 27.1.4Vulnerablenextcloud
  • cpe:2.3:a:nextcloud:nextcloud_server:*:*:*:*:enterprise:*:*:* Versions 23.0.0 to before 23.0.12.13; 24.0.0 to before 24.0.12.9; 25.0.0 to before 25.0.13.4 Vulnerable ·nextcloud
  • cpe:2.3:a:nextcloud:nextcloud_server:*:*:*:*:-:*:*:* Versions 26.0.0 to before 26.0.9 Vulnerable ·nextcloud
  • cpe:2.3:a:nextcloud:nextcloud_server:*:*:*:*:enterprise:*:*:* Versions 26.0.0 to before 26.0.9 Vulnerable ·nextcloud
  • cpe:2.3:a:nextcloud:nextcloud_server:*:*:*:*:-:*:*:* Versions 27.0.0 to before 27.1.4 Vulnerable ·nextcloud
  • cpe:2.3:a:nextcloud:nextcloud_server:*:*:*:*:enterprise:*:*:* Versions 27.0.0 to before 27.1.4 Vulnerable ·nextcloud

Remediation

  • Fix · CNA security-advisories (nextcloud) Fixed in 23.0.12.13, 24.0.12.9, 25.0.13.4, 26.0.9, 27.1.4

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-2023-49792

References

Patch 1

Advisory 1

Other 1

  • 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