CVE-2026-45543

Nextcloud: Deleting a Forms collaborator share leaves uploaded response files accessible through a lingering Files share

CVSS 5.3 MEDIUMEPSS 0.3%CWE-552

Vexday Risk Score

13Low

SSVC decision (CISA)

Track

No exploitation signal → monitor

CVSS 5.3EPSS 0.3%KEV nãoPoC —Nuclei —Metasploit —Patch —

Lifecycle

01 Jun 2026Published on NVD

Recommendation: Monitor — no exploitation signal at the moment.

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:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N

Affected products

nextcloud · security-advisories

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References

https://github.com/nextcloud/forms/pull/3291 https://github.com/nextcloud/security-advisories/security/advisories/GHSA-q4fw-6jf8-5vhh https://hackerone.com/reports/3617352