CVE-2026-45286 (GCVE-0-2026-45286)
Vulnerability from cvelistv5
Published
2026-06-01 16:59
Modified
2026-06-01 19:13
Severity ?
4.3 (Medium) - CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:N
CWE
  • CWE-200 - Exposure of Sensitive Information to an Unauthorized Actor
Summary
Nextcloud is an open source content collaboration platform. From versions 5.5.13 to before 5.5.17, and 6.2.0 to before 6.2.3, an authenticated user can enumerate users on the same Nextcloud instance by using the Calendar app's endpoint for suggesting attendees. The sharing restrictions, applied to other endpoints, were not effective here. This issue has been patched in versions 5.5.17 and 6.2.3.
References
Impacted products
Vendor Product Version
nextcloud security-advisories Version: >= 5.5.13, < 5.5.17
Version: >= 6.2.0, < 6.2.3
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                "id": "CVE-2026-45286",
                "options": [
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                "timestamp": "2026-06-01T19:12:56.174122Z",
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        }
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      "metrics": [
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            "attackComplexity": "LOW",
            "attackVector": "NETWORK",
            "availabilityImpact": "NONE",
            "baseScore": 4.3,
            "baseSeverity": "MEDIUM",
            "confidentialityImpact": "LOW",
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            "userInteraction": "NONE",
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          "name": "https://github.com/nextcloud/security-advisories/security/advisories/GHSA-r697-74m9-gvf2",
          "tags": [
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          "url": "https://github.com/nextcloud/security-advisories/security/advisories/GHSA-r697-74m9-gvf2"
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          "tags": [
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    "dateReserved": "2026-05-11T20:14:43.200Z",
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    "state": "PUBLISHED"
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  "dataType": "CVE_RECORD",
  "dataVersion": "5.2"
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