Nextcloud Server up to 32.0.8/33.0.2 access control

Summaryinfo

A vulnerability marked as critical has been reported in Nextcloud Server up to 32.0.8/33.0.2. The impacted element is an unknown function. This manipulation causes access control. This vulnerability appears as CVE-2026-45157. The attack may be initiated remotely. There is no available exploit. It is suggested to upgrade the affected component.

Detailsinfo

A vulnerability was found in Nextcloud Server up to 32.0.8/33.0.2. It has been declared as critical. Affected by this vulnerability is an unknown code. The manipulation with an unknown input leads to a access control vulnerability. The CWE definition for the vulnerability is CWE-284. The product does not restrict or incorrectly restricts access to a resource from an unauthorized actor. As an impact it is known to affect confidentiality, integrity, and availability. The summary by CVE is:

Nextcloud is an open source content collaboration platform. In Nextcloud Server from versions 32.0.0 to before 32.0.9, and 33.0.0 to before 33.0.3, when a malicious user has access to a file share of a user, they could use this share token to also access the chunking upload directly and see temporary part files during on going uploads. It is recommended that the Nextcloud Server is upgraded to 32.0.9 or 33.0.3. It is recommended that the Nextcloud Enterprise Server is upgraded to 26.0.13.26, 27.1.11.25, 28.0.14.17, 29.0.16.16, 30.0.17.9, 31.0.14.5, 32.0.9 or 33.0.3

The advisory is shared at github.com. This vulnerability is known as CVE-2026-45157 since 05/08/2026. The exploitation appears to be easy. The attack can be launched remotely. Neither technical details nor an exploit are publicly available. MITRE ATT&CK project uses the attack technique T1068 for this issue.

Upgrading to version 32.0.9 or 33.0.3 eliminates this vulnerability. Applying a patch is able to eliminate this problem. The bugfix is ready for download at github.com. The best possible mitigation is suggested to be upgrading to the latest version.

If you want to get the best quality for vulnerability data then you always have to consider VulDB.

Productinfo

Type

• Cloud Software

Vendor

• Nextcloud

Name

• Server

Version

• 32.0.0
• 32.0.1
• 32.0.2
• 32.0.3
• 32.0.4
• 32.0.5
• 32.0.6
• 32.0.7
• 32.0.8
• 33.0.0
• 33.0.1
• 33.0.2

License

• open-source

Website

• Product: https://github.com/nextcloud/server/

CPE 2.3info

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CPE 2.2info

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