CVE-2023-26482

2023-03-3019:15:06

Google

osv.dev

nextcloud

server

scope validation

unauthorized users

malicious workflows

remote code execution

rce

upgrade

mitigation

CVSS3

Attack Vector

NETWORK

Attack Complexity

LOW

Privileges Required

LOW

User Interaction

REQUIRED

Scope

CHANGED

Confidentiality Impact

HIGH

Integrity Impact

HIGH

Availability Impact

HIGH

CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:H/I:H/A:H

AI Score

6.9

Confidence

High

EPSS

0.002

Percentile

52.4%

JSON

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.