Medium severity · published Jun 1, 2026
CVE-2026-45267
Nextcloud: Missing permission check for from submissions
6.5
CVSS
0.3%
EPSS
No
On KEV
Description
Nextcloud is an open source content collaboration platform. Prior to version 5.2.6, a missing permissions check allowed users to request reading form submissions of other users. This issue has been patched in version 5.2.6.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N
Attack vector
Network
Complexity
Low
Privileges
Low
User interaction
None
Confidentiality
High
Integrity
None
Availability
None
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.3% · higher than 21% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
SE
security-advisories · nextcloud
< 5.2.6 · source: vendor
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-45267
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-45267
github.com
https://github.com/nextcloud/forms/pull/3269
github.com
https://github.com/nextcloud/security-advisories/security/advisories/GHSA-r4gh-f8x6-m55f
hackerone.com
https://hackerone.com/reports/3628817
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