CVE-2026-45264 Nextcloud: ACL Rename Permission Bypass in Team Folders Allows Unauthorized File Renames
Users with read and create permissions can rename files in team folders despite lacking update permissions, allowing unauthorized file modifications.
- Exploited in the wild
- Not known
- Login needed
- Any signed-in user
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- None listed
What is CVE-2026-45264?
CVE-2026-45264 is a medium-severity missing authorization vulnerability in nextcloud security-advisories, published on 1 Jun 2026. Any signed-in user can exploit it over the network, with no action from the victim.
Official description
Nextcloud is an open source content collaboration platform. From versions 17.0.0 to before 17.0.15, 18.0.0 to before 18.1.12, 19.0.0 to before 19.1.16, 20.0.0 to before 20.1.11, and 21.0.0 to before 21.0.4, a user with READ and CREATE permission, but no UPDATE permission for a team folder can rename files in the team folder. This issue has been patched in versions 17.0.15, 18.1.12, 19.1.16, 20.1.11, and 21.0.4.
Weakness: CWE-284
Which versions are affected by CVE-2026-45264?
How do I fix CVE-2026-45264?
No fix has been published for CVE-2026-45264 yet. Limit exposure of the affected software until one is available.
Upgrade, and check permissions on every request on the server, not only in the interface. More about Missing authorization.
Is CVE-2026-45264 being exploited?
There is no known exploitation of CVE-2026-45264 in the wild and no public exploit code.
Sources
Also known as GHSA-wx2x-822r-rvmf.