CVE-2025-66550 (GCVE-0-2025-66550)
Vulnerability from cvelistv5
Published
2025-12-05 16:56
Modified
2025-12-05 18:41
Severity ?
VLAI Severity ?
EPSS score ?
CWE
- CWE-241 - Improper Handling of Unexpected Data Type
Summary
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.
References
Impacted products
| Vendor | Product | Version | ||
|---|---|---|---|---|
| nextcloud | security-advisories |
Version: >= 5.0.0-rc.1, < 5.2.4 Version: < 4.7.17 |
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Sightings
| Author | Source | Type | Date |
|---|
Nomenclature
- Seen: The vulnerability was mentioned, discussed, or seen somewhere by the user.
- Confirmed: The vulnerability is confirmed from an analyst perspective.
- Published Proof of Concept: A public proof of concept is available for this vulnerability.
- Exploited: This vulnerability was exploited and seen by the user reporting the sighting.
- Patched: This vulnerability was successfully patched by the user reporting the sighting.
- Not exploited: This vulnerability was not exploited or seen by the user reporting the sighting.
- Not confirmed: The user expresses doubt about the veracity of the vulnerability.
- Not patched: This vulnerability was not successfully patched by the user reporting the sighting.
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