CVE-2025-66511 (GCVE-0-2025-66511)
Vulnerability from cvelistv5
Published
2025-12-05 16:42
Modified
2025-12-05 16:53
Severity ?
VLAI Severity ?
EPSS score ?
CWE
- CWE-330 - Use of Insufficiently Random Values
Summary
Nextcloud Calendar is a calendar app for Nextcloud. Prior to 6.0.3, the Calendar app generates participant tokens for meeting proposals using a hash function, allowing an attacker to compute valid participant tokens, which allowed them to request details and submit dates in meeting proposals. The tokens are not purely random generated. This vulnerability is fixed in 6.0.3.
References
Impacted products
| Vendor | Product | Version | ||
|---|---|---|---|---|
| nextcloud | security-advisories |
Version: >= 6.0.0-rc.1, < 6.0.3 |
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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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