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CVE-2025-66550 Detail

Description

Nextcloud Calendar is a calendar app for Nextcloud. Prior to 4.7.17 and 5.2.4, when a malicious user creates a calendar event with a crafted attachment that links to a download link of a file on the same Nextcloud server, the file would be downloaded without the user confirming the action. This vulnerability is fixed in 4.7.17 and 5.2.4.


Metrics

NVD enrichment efforts reference publicly available information to associate vector strings. CVSS information contributed by other sources is also displayed.
CVSS 4.0 Severity and Vector Strings:

NIST CVSS score
NIST: NVD
N/A
NVD assessment not yet provided.

References to Advisories, Solutions, and Tools

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URL Source(s) Tag(s)
https://github.com/nextcloud/calendar/commit/63a6c398db01391eb9fd5297a0d4c3d6e614f769 GitHub, Inc.
https://github.com/nextcloud/calendar/pull/6971 GitHub, Inc.
https://github.com/nextcloud/security-advisories/security/advisories/GHSA-f29c-ppmv-8mcv GitHub, Inc.
https://hackerone.com/reports/3112033 GitHub, Inc.

Weakness Enumeration

CWE-ID CWE Name Source
CWE-241 Improper Handling of Unexpected Data Type GitHub, Inc.  

Change History

1 change records found show changes

Quick Info

CVE Dictionary Entry:
CVE-2025-66550
NVD Published Date:
12/05/2025
NVD Last Modified:
12/05/2025
Source:
GitHub, Inc.