TI-2025-40937 Aliases CVE-2025-66515

Nextcloud Approval app allows users to request approval for other users file

LOW 14CWE-287Published 2025-12-05 · Updated 2025-12-05

Key facts

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

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

Summary

The Nextcloud Approval app allows approval or disapproval of files in the sidebar. Prior to 1.3.1 and 2.5.0, an authenticated user listed as a requester in a workflow can set another user’s file into the “pending approval” without access to the file by using the numeric file id. This vulnerability is fixed in 1.3.1 and 2.5.0.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV

EPSS 0.00335 27th percentileScored 2026-11-07

Fix Fixed security-advisories (nextcloud): 2.5.0, 1.3.1

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation: None
Automatable: No
Technical impact: Partial

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

Affected products

Vendor	Product	Affected versions	Fixed in	Status	Source
nextcloud	security-advisories	2.0.0 to before 2.5.0; before 1.3.1	2.5.0, 1.3.1	Patch available	CNA

security-advisories Vendornextcloud Affected 2.0.0 to before 2.5.0; before 1.3.1 Fixed in 2.5.0, 1.3.1 Patch available CNA

CPE configurations NVD · 1

CPE	Versions	Role	Vendor
cpe:2.3:a:nextcloud:approval::::::nextcloud::*	1.0.0 to before 1.3.1; 2.0.0 to before 2.5.0	Vulnerable	nextcloud

cpe:2.3:a:nextcloud:approval:*:*:*:*:*:nextcloud:*:* Versions 1.0.0 to before 1.3.1; 2.0.0 to before 2.5.0 Vulnerable ·nextcloud

Remediation

Fix · CNA security-advisories (nextcloud) Fixed in 2.5.0, 1.3.1

Timeline

2026-10-02 Threatist record created from CVE-2025-66515

References

Patch 2

Advisory 1

https://hackerone.com/reports/3338748

Other 1

https://github.com/nextcloud/approval/pull/334

TI-2026-33077 Nextcloud: Authorization bypass in approval feature allows unauthorized file sharing with approvers CVSS 3.1MEDIUM 6.5
TI-2026-33078 Nextcloud: Information disclosure in Nextcloud Approval app via fileId parameter reveals workflow associations CVSS 3.1LOW 3.3

Sources

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