Medium 5.3Published Jun 1, 2026

CVE-2026-45543Nextcloud: Deleting a Forms collaborator share leaves uploaded response files accessible through a lingering Files share

Updated under an hour ago (Oct 27, 2026, 3:30 AM ET)

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It affects nextcloud security-advisories and 1 other product. Add what you run to find out whether that includes you.

No exploitation reported and no EPSS estimate yet.

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Every CVE for nextcloud security-advisories

Exploited in the last 30 days

Nextcloud is an open source content collaboration platform. From version 4.3.0 to before version 5.2.7, a removed collaborator retains unauthorized read access to uploaded respondent files for the affected form. The scope is limited to uploaded files for forms where that user previously had results access. This issue has been patched in version 5.2.7.

CVSS: 5.3 MEDIUM (v3.1, CNA)CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N
Weakness (CWE): CWE-552
Known exploited: Not in CISA's KEV catalog
EPSS (exploitation in the next 30 days): Not loaded for this CVE
Assigned by: GitHub_M
NVD analysis: Analyzed
Record last updated: Jun 1, 2026
First seen by InfoSec Signals: Oct 9, 2026

Affected products

Affected products

nextcloud security-advisories nextcloud:security_advisories (from the name)	from 4.3.0, < 5.2.7	CNA record
nextcloud forms nextcloud:forms	from 4.3.0 before 5.2.7	NVD

References

References

https://github.com/nextcloud/security-advisories/security/advisories/GHSA-q4fw-6jf8-5vhh	x-refsource-confirm, mitigation, vendor-advisory
https://github.com/nextcloud/forms/pull/3291	x-refsource-misc, issue-tracking, patch
https://hackerone.com/reports/3617352	x-refsource-misc, permissions-required

The CVE record on cve.org NVD's entry

The CVE record is authoritative. Products marked “from the name” were identified from the CNA's free-text names, not a CPE, and are matched less certainly. This product uses the NVD API but is not endorsed or certified by the NVD.