CVE-2023-26482 Scope of workflow operations is not validated in nextcloud server
Missing scope validation allows users to create admin-only workflows, potentially leading to remote code execution if specific apps are enabled.
- Exploited in the wild
- Not known
- Login needed
- Any signed-in user
- Attackable
- Over the internet
- Victim action needed
- A user has to click or open something
- Fix
- None listed
What is CVE-2023-26482?
CVE-2023-26482 is a critical missing authorization vulnerability in Nextcloud Nextcloud Server, published on 30 Mar 2023. Any signed-in user can exploit it over the network, and only if a user opens a file or follows a link.
Official description
Nextcloud server is an open source home cloud implementation. In affected versions a missing scope validation allowed users to create workflows which are designed to be only available for administrators. Some workflows are designed to be RCE by invoking defined scripts, in order to generate PDFs, invoking webhooks or running scripts on the server. Due to this combination depending on the available apps the issue can result in a RCE at the end. It is recommended that the Nextcloud Server is upgraded to 24.0.10 or 25.0.4. Users unable to upgrade should disable app `workflow_scripts` and `workflow_pdf_converter` as a mitigation.
Weakness: CWE-78
Which versions are affected by CVE-2023-26482?
It affects 1 product.
Products include Nextcloud Nextcloud Server.
How do I fix CVE-2023-26482?
No fix has been published for CVE-2023-26482 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-2023-26482 being exploited?
It is not confirmed as exploited in the wild, but public exploit code for CVE-2023-26482 exists.
Public exploit code: 1 Metasploit module and 1 proofs of concept on GitHub.
Other vulnerabilities in Nextcloud Nextcloud Server
- CVE-2021-32802 Preview generation used third-party library not suited for user-generated content in Nextcloud server
- CVE-2018-3775 Auth bypass in Nextcloud Server
- CVE-2023-35172 Nextcloud Server password reset endpoint is not brute force protected
- CVE-2023-32320 Nextcloud Server's brute force protection allows someone to send more requests than intended
- CVE-2021-32656 Trusted servers exchange can be triggered by attacker
Sources
Also known as GHSA-h3c9-cmh8-7qpj.